Free Finance Calculators
Finance calculators with the formula shown alongside every result.
Money maths, without the sales pitch
Most financial calculators on the web exist to sell you something. The loan calculator sits on a lender's site and quietly assumes their rate. The mortgage tool wants your email before it shows the total. The result is that a simple question — what would the monthly payment be? — turns into a lead-generation form.
These do the arithmetic and stop. No account, no email, no broker waiting at the end. You get the number, the formula that produced it, and nothing else.
Why the formula is always shown
A financial calculator that only shows a result asks you to trust it about something that affects real money. Every tool here prints the working alongside the answer: the annuity formula and the values put into it, the division used to strip VAT out of a gross price, the exact percentages applied.
That matters most where intuition misleads. Removing VAT is the standard example. If a price includes 25% VAT, the VAT portion is not 25% of the gross — it is the gross divided by 1.25, and the difference is the tax. Subtracting 25% instead is a mistake that appears in a surprising number of spreadsheets, and seeing the division written out is what stops it.
What these tools deliberately do not do
They do not give advice. A calculator can tell you that a loan costs €4,200 in interest over five years; it cannot tell you whether that is a good idea, whether you would be better overpaying, or whether the lender's fees make a cheaper headline rate more expensive overall. Those questions need context and, often, a regulated professional.
They also do not model tax positions, currency movements, or anything that depends on live market data. Nothing here fetches a rate from anywhere, because everything runs on your own device — which is the trade-off that makes the privacy guarantee possible.
Why the privacy matters more here
People put unusually sensitive numbers into financial calculators. A salary. Outstanding debt. The size of a deposit. How much a business turns over. On a conventional site, every one of those figures is posted to a server, and on a lender's site it is a lead record before you have agreed to anything.
On this site the figures never leave the browser tab. There is no server to receive them and no log to keep them. You can verify it in about fifteen seconds: open your browser's network panel and watch it stay silent while you type. That is a property you can check rather than a promise you have to take on faith.
Rounding, and why totals sometimes look a cent out
Money is decimal, computers are binary, and the two do not divide evenly. A repayment schedule calculated to full precision and then rounded for display can produce a final balance a cent away from zero. Our amortisation table handles this the way lenders do: the last instalment absorbs the drift, so the balance lands exactly on zero.
Your own lender may round each instalment slightly differently, which is why a schedule here can differ from theirs by a few cents across the term. The totals will agree; the individual rows may not to the last decimal.
What is coming
Compound interest, mortgage repayments including overpayments, salary conversion between hourly, monthly and annual, discount and sale price, margin and markup, and a tip splitter. Each ships only once its edge cases behave — a finance calculator that is right most of the time is worse than none at all.
Frequently asked questions
Are these calculators accurate?
The arithmetic is exact, and every tool shows the formula it applied so you can check it. What they cannot know is your circumstances — a real loan offer includes arrangement fees, insurance, and a lender's own rounding rules, none of which appear in a standard repayment formula. Treat the output as the mathematical answer, not as a quote.
Is this financial advice?
No. These are calculators, not advisers. They tell you what a number works out to; they cannot tell you whether a loan is affordable or a purchase is wise. For decisions that matter, talk to someone qualified and regulated in your country.
Is my financial information sent anywhere?
No. Every figure you type is processed by JavaScript in your own browser and is never transmitted. Nothing is stored either — close the tab and the numbers are gone. Given people put salaries, debts and loan amounts into these tools, that is the whole reason they are built this way.
Why is there no currency converter?
Exchange rates change by the minute and would require fetching live data from a server, which breaks the offline, nothing-leaves-your-device model. Every calculation here uses fixed arithmetic that needs no network.
Which currency do these use?
None in particular. The maths is identical whatever the currency, so the tools show plain numbers and leave the symbol to you. Amounts are formatted using your browser's locale, so the thousands and decimal separators match what you are used to.
Do the VAT rates stay up to date?
They are checked and dated, and the tool shows when. Rates change by legislation, so for anything you are filing, confirm against the national tax authority. You can always type a custom rate.