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Pricing
Prices, margins and discounts — the numbers that decide whether a sale is worth making.
Business & money tools
The money maths behind every small decision.
BusinessLipTools is a workbench of calculators for the figures a business runs on: the margin inside a price, the tax inside a total, the true cost of a loan, the day rate a freelancer needs before the year stops adding up. Each tool is one page with one job. Open it, enter your figures, read the answer with its working shown — then close the tab and get back to the business.
- No account
- Nothing uploaded
- Method shown, not hidden
Invoice INV-2026-014Harbour Fitness Group
| Brand workshop — facilitation | $1,400.00 |
| Follow-up report | $650.00 |
| Subtotal | $2,050.00 |
| VAT at 20% | $410.00 |
| Total due | $2,460.00 |
Built with the invoice generator — discount and tax applied in the right order, totals updating as you type.
A business rarely fails on its craft. It fails on a figure nobody checked — a price set by feel, a loan judged by its instalment, a rate that forgot the unpaid hours. Check the figure first.
Categories
Five shelves, twenty calculators
Money questions arrive in families. Pricing questions are about what a sale leaves behind; tax questions are about which part of a total was never yours; loan questions are about time as much as money. The shelves below keep those families together, and every calculator carries the same promise: the inputs on the left, the answer on the right, and the method written underneath so you can argue with it.
VT
Tax
VAT, GST, sales tax and withholding, worked out on the amount you actually have.
EMI
Loans & Interest
Borrowing and growing money: instalments, interest and how long payback really takes.
ROI
Decisions
ROI, break-even, late fees and the rate a freelancer actually needs to charge.
S⇄H
Office & Paperwork
Pay conversions, working-day counts, amounts in words and a printable invoice.
Category guides
What each shelf is for, in plain terms
A calculator answers the question you ask it. These short guides are about asking the right one — what each family of tools measures, where its numbers come from, and the mistake that family exists to prevent.
Pricing: the shelf that decides if a sale is worth it
Every price is two numbers wearing a coat: what the thing costs you and what the customer hands over. The space between them funds everything else in the business, so this shelf is built around protecting it. The margin calculator measures profit against the selling price, the base accountants use. The markup calculator works the other way, building a price up from cost — and translates it into margin, because a 50% markup and a 50% margin are different worlds that are confused daily.
The discount calculator exists because promotions are where good margins go to be given away by accident: stacked percentages multiply instead of adding, and tax follows the discounted price, not the ticket. The price-per-unit calculator settles the quieter argument — which pack, which supplier, which bulk offer is genuinely cheaper once everything is reduced to the same unit. Reach for this shelf before any price is printed, quoted or published, not after.
Tax: the shelf for money that was never yours
Indirect tax has one property that causes most of its errors: it travels inside prices. A total on a receipt is a mixture of your money and the state's, and the proportions are set by a rate applied to the net amount — which is why extracting tax from a gross figure means dividing, not subtracting a percentage. The VAT and GST calculators both work in both directions, and the GST tool also splits the tax into the two equal halves some systems print on invoices.
The sales tax calculator handles the layered American version, where state and local rates stack on one base. The withholding calculator covers the mirror image: money a client keeps back from your invoice and pays over in your name. It is your money and usually your tax credit, but it is not in your bank account, and this shelf keeps that distinction numerically visible — gross, withheld and net, side by side.
Loans & interest: the shelf where time is the price
Borrowing and saving are the same machine running in opposite directions, and the machine's fuel is time on a balance. The EMI calculator shows the fixed instalment a loan really needs and the total interest hiding behind it, with a year-by-year balance so you can watch the debt's slow start and fast finish. The compound interest calculator runs the machine for savers, with the regular monthly contribution that real saving actually consists of.
Next to them sit two deliberately simpler tools. The simple interest calculator is the straight-line method still used in short-term arrangements and late-payment clauses, and comparing its output with the compound tool at the same rate is the fastest way to feel what compounding does. The payback calculator answers a different question entirely — not what an investment earns, but how long your money is out of the house before it has repaid itself.
Decisions: the shelf for go / no-go numbers
Some figures exist to settle an argument. The break-even calculator settles “how much do we need to sell?” by splitting costs into the fixed pile and the per-unit cost, then counting sales until the pile is covered. The ROI calculator settles “was it worth it?” — and, when you give it the holding period, annualises the answer so a three-year project can be compared with a one-year one without self-deception.
The late payment fee calculator prices what an overdue invoice has earned in interest and fees, part by part, because a fee you cannot itemise is a fee you cannot defend. The freelance rate calculator settles the hardest argument of all — what to charge — by working backwards from the income you need to keep, through tax, overheads and the unpaid hours nobody mentions, to the rate below which your year cannot work.
Office & paperwork: the shelf that ends arguments
The last shelf is clerical, and proudly so: these tools produce the numbers and documents that pass between businesses, where a small error is copied faithfully into somebody else's system. The salary converter translates between annual and hourly frames so two offers can be compared in the same units. The business days calculator counts the working days inside a deadline, because “ten business days” and “ten days” part company quickly in December.
The amount-in-words converter writes a figure out in full for cheques and contracts — the form that prevails when words and digits disagree — and the invoice generator assembles the whole document: parties, lines, discount, tax, total, ready to print. Nothing on this shelf is glamorous. It is the shelf that stops payments bouncing between inboxes over a missing detail, which is most of what paperwork is for.
Featured tools
Eight regulars, opened up
These are the calculators that earn their place in a working week. Each card below describes not just what the tool returns but how it gets there and where its answer stops being the whole story — because a figure you cannot interrogate is a figure you should not sign.
%
Profit Margin Calculator
PricingThe margin calculator takes the two figures every sale is made of — what a unit costs you and what it sells for — and separates the three percentages that are constantly mistaken for one another: gross profit in money, margin as a share of the price, and markup as a share of the cost. It is the fastest health check a product can get.
How it works
Type a cost and a price and all three figures update together. The relationship between them is exact, so watching them move as you nudge the price is genuinely instructive: a small price rise lifts margin slowly but cuts nothing else, while the same money taken off cost lifts margin by precisely the same amount — the calculator makes that symmetry visible instead of leaving it as a claim.
The method
Margin is profit divided by selling price; markup is profit divided by cost. The two are linked by margin = markup ÷ (1 + markup), which is why a 100% markup is a 50% margin and why margin can approach but never reach 100%. These are gross figures: they cover the direct cost of the unit and nothing else.
Where it stops
Gross margin does not know about your rent, your wages, your card fees or your tax. A product can carry a handsome gross margin while the business loses money, because everything below the gross line still has to be paid. Treat this figure as the first filter — a product that fails here cannot be saved by volume — not as the verdict on the business.
Cost $60.00 → Price $100.00profit $40.00
Margin (on price)40.00%
Markup (on cost)66.67%
VT
VAT Calculator
TaxThe VAT calculator works in both directions: adding tax to a net figure to build an invoice total, and extracting the tax already hiding inside a gross figure — a receipt, a shelf price, a competitor’s quote.
How it works
Pick a direction and a rate. Adding is straightforward multiplication. Removing divides the gross by one plus the rate to recover the net, then reports the tax as the difference — all three figures stated, the way returns and invoices both demand them.
The method
VAT is charged on the net amount, so the tax inside 120 at 20% is 20, not 24. Any method that subtracts the percentage from the total double-counts the tax on the tax, and the difference lands in somebody’s return.
Where it stops
It cannot tell you which rate applies to what you sell, whether you should be registered, or how your jurisdiction treats a particular supply. Rates and rules are inputs you bring; the tool’s job is flawless arithmetic on the pair you choose.
Net $100.00+ VAT 20%
Gross total$120.00
Reverse: $120.00 grossVAT inside = $20.00
−%
Discount Calculator
PricingThe discount calculator prices a promotion before it costs you: the sale price, the customer’s saving, a second stacked discount if the offer has one, and the tax charged on the reduced price.
How it works
Each discount acts on the price the previous one left behind, and the tool follows that chain in the correct order — discounts first, tax last. When you stack two offers it also reports the true combined percentage, which is never the sum of the two numbers on the banner.
The method
Two successive discounts of d1 and d2 remove (1 − (1−d1)(1−d2)) of the price: 20% then 10% is 28% off, not 30%. Planning a sale on the additive assumption misprices every unit in it, in whichever direction hurts.
Where it stops
It prices the offer, not its wisdom. Whether a discount buys enough extra volume to pay for itself depends on your margin and your customers, and no calculator can see either. Run the result through the margin calculator before the banners go up.
List $120.00−25%−10% extra
Customer pays$81.00
True saving32.50%, not 35%
EMI
Loan EMI Calculator
Loans & InterestThe EMI calculator turns a loan offer into its three honest numbers: the monthly instalment, the total interest across the whole term, and the balance remaining at the end of each year.
How it works
Enter the amount, the annual rate and the term in months. A year-by-year table then shows principal repaid, interest paid and balance — the shape of the debt over time, which is where the real differences between two loan offers live.
The method
The instalment uses the reducing-balance formula: EMI = P·r·(1+r)ⁿ ÷ ((1+r)ⁿ − 1), where r is the monthly rate. Interest each month is charged only on the balance still owed, so early payments are mostly interest and later ones mostly principal, without any penalty or trick being involved.
Where it stops
Arrangement fees, bundled insurance, early-repayment charges and variable rates all sit outside this formula — and a variable rate makes any fixed projection provisional. Compare competing loans on total repaid under the same term, then read the offer documents for the parts no calculator can see.
Borrow $25,000 · 9% · 60 monthsEMI $518.96
Total interest$6,137.53
Balance after year 1$20,854.25
CI
Compound Interest Calculator
Loans & InterestThe compound interest calculator projects what a savings habit becomes: a starting amount, a rate, a term, your choice of compounding frequency, and — the input most projections omit — a regular monthly contribution.
How it works
The starting sum compounds at the chosen frequency. Contributions are added at the start of each month and converted to that frequency at the equivalent rate, so switching between monthly and yearly compounding keeps the comparison honest rather than flattering one side.
The method
Growth follows FV = P(1 + r/n)ⁿᵗ for the lump sum, with the contribution stream accumulated as an annuity. The output separates what you paid in from what growth added, because the single most useful fact in any projection is how much of the ending figure you actually funded yourself.
Where it stops
It assumes one unchanging rate, no tax on the growth, no fees and no withdrawals. Real accounts violate all four, in different directions. Use it to compare strategies under identical assumptions — starting earlier versus paying in more — where the comparison survives even though the forecast cannot be exact.
$5,000 + $200/month · 7% · 10 yrs
You put in$29,000.00
Projected value$44,867.20
BE
Break-Even Calculator
DecisionsThe break-even calculator counts the sales a business must make before it stops losing money: fixed costs divided by what each sale contributes after its own costs.
How it works
Enter the fixed pile for a period, the price per unit and the variable cost per unit. Add the volume you actually expect and the tool shows the profit or loss waiting at that level — the distance between plan and safety, in money.
The method
Each sale contributes price minus variable cost. Break-even units = fixed costs ÷ contribution margin, rounded up, because you cannot sell a fraction of a unit and the pile is only covered by a whole sale. Revenue at break-even follows from the unit count, not the other way round.
Where it stops
The model assumes one product, steady prices and costs that divide cleanly into fixed and variable. Real businesses are messier — product mixes shift and costs come in steps. Treat the answer as the centre of a range: rerun it with a worse price and a higher variable cost and see whether the business still stands.
Fixed $6,000 · price $45 · variable $27
Contribution$18.00 / unit
Break-even334 units · $15,030
FR
Freelance Rate Calculator
DecisionsThe freelance rate calculator works backwards from the life you intend to fund: a target income to keep, plus overheads, grossed up for tax, divided by the hours you can honestly sell. Out comes the rate below which your year cannot work.
How it works
Every input is exposed — weeks off, working days, hours per day, and the billable percentage, the share of your time a client actually pays for. Change the billable share and watch the required rate move: it is the lever most new freelancers set by optimism and pay for by December.
The method
Required revenue = (target income + overheads) ÷ (1 − tax reserve). Billable hours = working weeks × days × hours × billable share. The division of the first by the second is the floor rate; the day rate is simply that figure times your hours in a day. Nothing in the method is clever, which is the point — the discipline is in refusing to flatter the inputs.
Where it stops
A floor is not a price. Clients pay for skill, scarcity and results, and the right price for a given engagement may sit far above the floor — or, for work with strategic value, knowingly below it for a while. What the floor gives you is the size of every concession, in numbers, before you make it.
Target $60,000 · overheads $6,000 · tax 20%
Billable hours (47 wks · 60%)1,128
Floor rate$73.14 / hr · $585.11 / day
INV
Invoice Generator
Office & PaperworkThe invoice generator assembles the document itself: your details, the client’s, numbered lines with quantities and rates, a discount, tax on the discounted amount, and a total — laid out cleanly enough to print or save as a PDF straight from the browser.
How it works
Totals recalculate as you type, and the preview is the document: what you see is what prints. Because everything runs on your device, the invoice exists only in front of you until you save it — client details never pass through a server to get typeset.
The method
The arithmetic follows standard invoicing order: subtotal first, discount off the subtotal, tax charged on what remains. That order is not universal in every trade, which is why the intermediate figures are shown in the totals panel rather than buried in a single sum.
Where it stops
It cannot number your invoices across sessions, chase late payers, or file anything with a tax authority — and it does not store the document when you close the page. Save the PDF with the job paperwork. An invoice you cannot find in March is an invoice you effectively never sent.
Lines: workshop $1,400 · report $650
Subtotal $2,050 · VAT 20% $410
Total due$2,460.00
Anatomy
Every calculator page is built the same way
Deliberately so. A pricing tool and a tax tool ask different questions, but the page around the question should not have to be relearned each time. Learn one page here and you have learned all twenty.
01
The figures panel
Your inputs, on the left, labelled in the words the trade uses for them — cost, rate, term — with the defaults set to a realistic example rather than zero, so the result panel is alive before you touch anything and you can see what a sensible answer looks like.
02
The result panel
The answer, on the right, updated as you type — no submit button, no page reload, no waiting. Where a decision needs more than one number, the panel shows the supporting figures too: total interest next to the instalment, the balance table under the summary, the parts of a fee itemised.
03
The method, underneath
Two short sections close every tool page: how the calculation works, in plain language with the formula where a formula exists, and where it stops — the assumptions, the exclusions, the point past which you need a professional. The shortest text on the page, and the part most worth reading before you quote the number to anyone.
This sameness is also a safety feature. If a calculator ever behaves differently from the pattern — a figure that does not update, a total you cannot reproduce from the method underneath — treat that as a fault and tell us. Consistency you can set your watch by is what makes an inconsistency visible.
In practice
Whole jobs, start to finish
Nobody wakes up wanting a percentage. They wake up with a job — a launch to price, a loan to judge, a year to make viable — that happens to need three or four percentages in a particular order. These are the runs we see most, written out in sequence.
Pricing a product launch
You know what the unit costs. You do not yet know whether the price in your head leaves the business alive at the volume you can actually sell. The order matters: margin first, then the promotion you are already planning, then the volume test.
Judging a loan offer
The bank quotes an instalment because instalments are easy to say yes to. Your job is to translate the offer into totals and time before deciding, and then to check what the same money would do if it were not servicing debt.
Setting a freelance rate that survives the year
A rate copied from another freelancer imports their costs, their tax and their holidays into your business. Build yours from your own figures instead, then sanity-check it against the salary you left and the invoices you will actually send.
Worked examples
Two calculations, done slowly
Formulas convince nobody. Here are the two questions this site is asked most, worked end to end with real-shaped numbers, so you can follow the money through every step — and check our arithmetic while you are at it.
Example 1 — Will this product line cover its costs?
A small studio sells a printed workbook. Each copy costs $27 all-in — print, packaging and the card fee on a typical order. The studio's fixed costs for the line are $6,000 a quarter: the design software, the storage unit and the market stall fees that are owed whether one copy sells or a thousand.
At a price of $45, each sale contributes 45 − 27 = $18 towards that fixed pile. The break-even count is 6,000 ÷ 18 = 333.3, and because a third of a workbook cannot be sold, the true figure rounds up: 334 copies, bringing in $15,030. At copy 334 the line has paid for itself; every copy after that contributes its full $18 to profit.
Now the sensitivity, which is the part worth the ink. Drop the price to $42 for a promotion and the contribution falls to $15: break-even climbs to 400 copies, a fifth more sales for the privilege of earning less per sale. Raise the variable cost by $2 — a paper price increase — and contribution becomes $16, needing 375 copies. Small numbers at the unit level, large numbers at the volume level: that leverage is the whole lesson of break-even analysis, and it is why the inputs deserve measuring rather than guessing.
Example 2 — From a loan quote to a decision
A bakery is offered $25,000 over five years at 9% to replace an oven. The instalment works out at $518.96 a month — a figure the bakery can picture. The totals are less picturable: 60 payments sum to $31,137.60, of which $6,137.53 is interest, roughly a quarter of the amount borrowed, paid for the use of the money over the term.
The balance table tells the second half of the story. After a full year of payments — $6,227.52 handed over — the balance has fallen only to about $20,854: barely $4,146 of principal cleared, because interest on a large balance eats the early instalments. By the end of year three the same monthly sum is clearing principal at roughly twice that pace. Nothing about this is unfair; it is what “interest on the outstanding balance” means when you watch it happen.
The decision then uses the other shelves. The new oven is expected to add about $9,500 a year in net cash — more capacity, less waste — so its payback is 25,000 ÷ 9,500 ≈ 2.6 years, comfortably inside the loan term: the asset repays its cost while the loan still has over two years to run, and the bakery is cash-positive on the oven before it is debt-free on it. That relationship — payback shorter than term, with margin to spare — is the shape of a borrowing decision that usually survives contact with reality.
Limits
Where each tool stops
A calculator that claims to settle everything is selling something. These are the edges of the main tools — the point past which the arithmetic is still right but the answer is no longer the whole answer.
- Profit Margin Calculator
- Gross margin only. It knows the unit's cost and price and nothing below that line — rent, salaries, marketing and tax are invisible to it. A shelf of healthy margins can still be a loss-making business, and this tool will not warn you, because the information never reaches it.
- VAT & GST Calculators
- The arithmetic is exact; the rate is your responsibility. These tools cannot know your product's classification, your registration status or this year's threshold in your country. If the rate you type is wrong, the answer is wrong with complete confidence and perfect formatting.
- Loan EMI Calculator
- A fixed rate for the whole term is assumed. Variable-rate loans, payment holidays, fees capitalised into the balance and early-repayment charges all bend the real schedule away from this one. Use it to compare offers on equal terms, then read the actual agreement for the bends.
- Compound Interest Calculator
- One steady rate, no tax, no fees, no withdrawals, contributions never missed. It is a projection machine for comparing strategies, not a forecast. Anyone who shows you a compounding curve without listing its assumptions is showing you advertising, not analysis.
- Break-Even Calculator
- One product, one price, costs split into exactly two kinds. Multi-product businesses break even on a mix, and the mix moves. Run the calculation per product line where you can, and treat a single blended figure as a compass heading rather than a map reference.
- ROI Calculator
- It cannot see risk, effort or timing beyond the annualisation you give it. Two ventures with identical ROI may differ in every way that matters — one may have nearly bankrupted its owner on the way. The percentage closes no argument by itself; it opens the right one.
- Late Payment Fee Calculator
- It prices the terms you enter. Whether those terms are enforceable — agreed in advance, within statutory caps, calculated on the correct base — is a legal question that varies by place, and some jurisdictions give debtors rights no contract can sign away. Arithmetic first, advice before enforcement.
- Invoice Generator
- It produces a clear document, not a compliant filing system. Numbering sequences, retention periods, e-invoicing mandates and tax-authority formats are yours to satisfy, and the document is gone when the tab closes unless you save it. Treat it as a typesetter with a calculator, not as your accounting system.
Choosing
Picking between lookalikes
Half the wrong figures in small business come from opening the wrong one of a similar pair. These are the pairs that get confused, and the question that separates them.
Margin or markup?
Profit Margin Calculator
Profit as a share of the selling price. The number for judging, comparing and reporting.
Markup Calculator
Profit as a share of the cost. The number for building a price up from what you pay.
The separating question: are you starting from a cost and building a price (markup), or starting from a price and judging it (margin)? Same profit, two different denominators — and a “50%” that means different money in each.
Simple or compound interest?
Simple Interest Calculator
Interest charged only on the original principal, in a straight line — short-term deals and penalty clauses.
Compound Interest Calculator
Interest earning interest, on a curve — savings, investments, anything left alone for years.
The separating question: does the interest itself start earning or owing interest? Over one year the two nearly agree; over ten, choosing the wrong one is not a rounding error, it is the difference between a line and a curve.
Payback or ROI?
Payback Period Calculator
How long until the investment has repaid its cost. A measure of exposure and risk.
ROI Calculator
How much the investment returned in total, as a percentage. A measure of reward.
The separating question: are you asking “how long is my money at risk?” or “how much did it make me?” A good investment usually needs a decent answer to both; a fast payback with a poor lifetime return is a treadmill, not a triumph.
Salary or freelance rate?
Salary to Hourly Converter
Translates an employed package into hourly terms — the same frame as a contract rate, nothing more.
Freelance Rate Calculator
Builds the rate a self-employed year actually requires, once tax, overheads and unpaid hours are inside it.
The separating question: are you converting a number, or funding a life? A converted salary is a comparison; a freelance rate is a budget. Matching your old hourly equivalent usually underprices the freelance year by the cost of everything employment used to provide.
Reference
Margin and markup, side by side
Pin this table to the wall; it settles the most common pricing argument in business. Because margin and markup divide the same profit by different bases, each markup corresponds to exactly one margin — and the gap between them widens as the numbers grow, which is why the confusion gets more expensive the better a product sells.
| If you add this markup… | …your margin is | And to earn this margin… | …you must charge this markup |
|---|---|---|---|
| 10% | 9.1% | 10% | 11.1% |
| 25% | 20.0% | 20% | 25.0% |
| 33.3% | 25.0% | 25% | 33.3% |
| 50% | 33.3% | 33.3% | 50.0% |
| 100% | 50.0% | 40% | 66.7% |
| 150% | 60.0% | 50% | 100.0% |
| 200% | 66.7% | 60% | 150.0% |
| 300% | 75.0% | 75% | 300.0% |
Read it in the direction of your mistake. If you priced with a 50% markup believing you had a 50% margin, the middle columns show the truth: you have 33.3%, and on a product turning over serious volume that missing sixth of the price is the difference between a healthy line and a mystery. If a platform or a retailer demands a 40% margin, the right-hand column shows the markup you must apply to your cost to deliver it — 66.7%, a figure that surprises almost everyone the first time.
The second reference worth keeping nearby is the shape of a loan. Any reducing-balance loan, at any rate, spends its first year paying down surprisingly little principal — on a five-year loan, typically well under a fifth of the debt — and its last year clearing principal at several times the early pace. When a balance seems to ignore your payments, compare it with the year-by-year table from the EMI calculator before suspecting an error: the schedule is lopsided by design, everywhere, and knowing that in advance is the difference between a plan and a grievance.
How it's built
Built like a ledger, not a funnel
- Principle 01
One page, one calculation
There is no dashboard, no project file and nothing to configure before a tool answers. Each calculator is a single page that takes the figures for one question and returns that question's answer, with the method attached.
- Principle 02
The method travels with the number
Every result on the site is accompanied by how it was produced and where it stops. A figure you cannot trace is a figure you cannot defend — to a client, to a bank, or to yourself in six months when the context has evaporated.
- Principle 03
Nothing to sign into
No accounts, no uploads, no tracking of what you calculate. Your loan figures and invoice totals are commercially sensitive in aggregate even when each is innocent alone, so the site is built to be incapable of collecting them: the arithmetic happens on your device, full stop.
CtrlK
Every calculator is two keys away
Press Ctrl+K from any page and type what you need — “margin”, “vat”, “payback”, “invoice”. The list narrows as you type; the arrow keys move; Enter opens. On a Mac it is Cmd+K. It is the fastest route across the workbench and it behaves identically on every page, because the pages were built to a pattern on purpose.
Missing
What is not on the bench yet
Honesty about the gaps is part of the method. Some of these are coming, some are waiting on a decision, and a few are refused on principle.
Live exchange rates — a currency converter needs rates that move hourly, and a static page quoting yesterday's rate with today's confidence would mislead exactly the people converting invoices. Not until a rate source exists that we would defend.
Full accounting — ledgers, reconciliation and filing belong to accounting software that stores your books. This site deliberately stores nothing, so the invoice generator stops at the document, on purpose.
Country-specific tax filing — return formats and thresholds differ by jurisdiction and change yearly. The tax shelf does arithmetic on the rate you supply rather than impersonating your tax authority.
Investment advice — the ROI and interest tools measure and project; they do not recommend. A page that cannot see your debts, your runway or your sleep has no business telling you where to put money.
Saved calculations — history needs accounts, and accounts would undo the site's core property. Bookmark the tool; recompute in seconds; keep the only copy of your figures where it belongs, with you.
Payroll for teams — payslips, deductions across a staff and statutory reporting are a regulated system, not a calculator. The salary converter covers the one-person version of the question and stops there.
Glossary
The vocabulary of the figures
Twelve terms that do the heavy lifting on this site, defined the way the calculators use them — because most money confusion is vocabulary confusion wearing numbers.
- Contribution margin
- The price of a unit minus the costs that grow with that unit. It is what each sale contributes towards fixed costs, and then to profit.
- Gross profit
- Revenue minus the direct cost of what was sold. It ignores every overhead below that line, which is both its use and its danger.
- Amortisation
- The schedule by which a loan is repaid in fixed instalments, each part interest on the balance and part repayment of it.
- Principal
- The amount borrowed or invested, before any interest touches it. Interest is always calculated on some version of this figure.
- Net / Gross (tax)
- Net is the amount before tax is added; gross is the amount with tax inside it. Converting between them is division, never subtraction of a percentage.
- Withholding
- Tax collected at the point of payment by the payer and credited to the earner, who receives the net and a certificate, not the gross.
- Billable hour
- An hour a client pays for. The billable share of a working year is always below 100%, and pricing that forgets this is pricing a fantasy.
- Fixed cost
- A cost that stays the same across a period whatever the sales volume — rent is the classic example. It is owed on your worst month too.
- Variable cost
- A cost that grows with each unit sold or delivered — materials, packaging, per-transaction fees. It defines the contribution margin.
- Break-even point
- The sales volume at which total contribution exactly covers total fixed costs. Below it, loss; above it, profit — with nothing in between.
- Annualised return
- A multi-year return restated as the equivalent steady yearly rate, so results over different periods can be compared without self-deception.
- Working capital
- The money tied up in the gap between paying your costs and being paid yourself. Late payment stretches it; prompt invoicing defends it.
Questions
The questions these figures raise
Do my figures leave my device?
No. There is no server component behind these calculators: the pages are static files, and every computation happens in the JavaScript running in your browser. Your loan amount, your salary and your invoice lines are never transmitted, logged or stored anywhere by this site. You can verify it rather than believe it — open your browser’s developer tools, switch to the network panel, and use any tool while watching: the only requests are the page files themselves, fetched when you arrived.
Why do margin and markup give different percentages on the same profit?
Because they divide the same profit by different amounts. Margin divides by the selling price, markup divides by the cost, and since the price is the larger number, the margin is always the smaller percentage. The trap is that the everyday sentence “we make fifty percent on this” hides which one is meant — and on a 100 cost sold at 150, the difference is between 50% (markup) and 33.3% (margin). Every pricing tool here shows the one you did not ask for alongside the one you did, precisely so the two cannot be silently swapped in a negotiation or a spreadsheet.
My break-even point looks too low. What am I probably doing wrong?
Almost always, a cost is sitting in the wrong bucket or missing entirely. The classic omissions are the owner’s own time (priced at zero), delivery and transaction fees treated as if they were fixed, and fixed costs counted monthly while the volume is counted quarterly. A second, quieter error is using the selling price before discounts and fees — the price you actually bank is the one that belongs in the formula. Correct the buckets before doubting the arithmetic: the formula is three operations, and it is nearly innocent in every dispute we have seen.
Can I rely on the EMI figure when I sign a loan?
You can rely on it as the exact instalment for the amount, rate and term you entered, on a reducing-balance basis — and you should then check the offer against it, because discrepancies do occur, usually from fees folded into the principal or a rate quoted on a different basis. What the figure cannot include is anything the formula has no input for: arrangement fees, bundled insurance, early-settlement charges, and rate changes on a variable product. Sign on the agreement’s own total-cost figure, and use this calculator as the independent check that keeps that figure honest.
Why does the freelance rate look so much higher than my old salary’s hourly equivalent?
Because it is carrying passengers the salary never showed you. The converter translates a salary that came with paid holidays, employer contributions, equipment, sick pay and a marketing department of zero, because clients arrived by themselves. The freelance rate must fund all of that from the same hours — and from only the billable share of them, since proposals, admin and gaps between engagements are unpaid. Divide a year’s true costs by a year’s true billable hours and the “high” rate is usually revealed as the honest one, and the salary comparison as the flattering one.
Is the tax inside a price really found by dividing?
Yes — because the tax was calculated on the smaller, pre-tax amount. A 20% tax on 100 produces a 120 total; the tax is a sixth of that total, not a fifth. Subtracting 20% from 120 removes 24 and invents a net of 96 that never existed. Dividing the gross by 1.20 returns the original 100 exactly, which is why both the VAT and GST calculators work that way, and why the error matters at scale: across a quarter of receipts, subtracting instead of dividing systematically misstates the tax you owe or can reclaim.
Are the projections from the interest calculators realistic?
They are arithmetically exact and deliberately unrealistic, and the pages say so. A projection holds one rate constant for years and ignores tax, fees, missed contributions and withdrawals; reality will differ in all five respects. Their legitimate use is comparison under identical assumptions — starting now versus in five years, this contribution versus that one — where the unrealistic parts apply equally to both sides and the difference between them is still meaningful. Anyone presenting a compounding curve as a forecast, rather than as a comparison, is selling the account, not explaining it.
What should an invoice include to get paid without queries?
The fields that accounts departments check before anything is approved: your legal business name and contact details, the client’s correct legal name, a unique invoice number, the issue date and the due date stated as a date rather than “on receipt”, a description of the work specific enough to match a purchase order, the tax treatment with the rate and amount shown separately, and the total. Most payment delay is not refusal — it is an invoice bouncing between inboxes because one of those is missing. The generator’s layout puts all of them on the page in the order a payer reads them.
Why does the business days calculator ask me for the number of holidays?
Because there is no universal holiday calendar to bake in. Public holidays differ by country, by region and occasionally by industry, and a built-in calendar would be confidently wrong for most visitors while looking authoritative. Asking you for the count — holidays that fall on weekdays inside your range — is less convenient and more honest. It also forces the assumption into the open, which matters when a contract deadline is disputed: “ten business days, excluding the two public holidays in that window” is a sentence that settles arguments.
Can a late payment fee be charged on any overdue invoice?
Only within the terms that govern that invoice and the law where you trade. In many places the rate must have been agreed before the work began, or a statutory rate applies by default; in some, the rate is capped; in a few, business-to-consumer invoices are treated differently from business-to-business ones. The calculator prices whatever terms you enter, separately and in the open, which is the part arithmetic can do. Whether those terms bind your debtor is a legal question — check your contract and, for significant sums, take advice before enforcing rather than after.
Do the tools work offline, and on a phone?
Once a page has loaded, yes: each calculator is self-contained, and the arithmetic runs the same with the network off as on — handy for the kitchen-table and site-visit end of small business. The layouts are built for phones as well as desktops, with inputs sized for thumbs. The invoice generator is the one partial exception in spirit rather than function: it works on a phone, but printing and saving its PDF is a more comfortable job on a larger screen.
What does the site cost, and what pays for it?
The tools are free, with no accounts and no feature reserved behind a payment. The site is cheap to run precisely because of how it is built — static pages, no database, no per-user computation on our side. If advertising appears in future, it will be disclosed in the privacy policy, and it will sit around the tools, never inside them: an advertiser will never see, and could never be given, the figures you type into a calculator, because those figures never leave your device in the first place.
Start with the figure you have been avoiding.
It is usually the margin on your best seller, the total interest on the loan, or the rate your year actually needs. Whichever it is, it takes about twenty seconds here, and the method is printed underneath it.