Calculators
Money and percentages, with the working shown underneath.
- See what a balance grows intoSet a starting sum, what you add each month, a rate and a term. The projected balance redraws as you change any of them.
- Work out a loan paymentPut in the amount, the rate and how long you have. The payment and what it costs you over the term appear as you type.
- Work out a percentageChoose the question you actually have. The answer and the working behind it redraw as you type.
About these tools
A calculator that returns one number is asking to be trusted about a decision worth thousands. These show the working instead: the schedule behind a monthly payment, the contributions and the interest separated out, the arithmetic behind a percentage that people most often get backwards.
The figures are checked against published examples rather than against themselves. Rounding is the part that quietly diverges, so where two conventions genuinely disagree the page says which one it uses and why — a lender rounds to the cent every month, and a savings projection that rounds the same way walks a little away from the closed-form figure people check against.
Everything runs as you type, so changing the rate is a question you can ask ten times in a row rather than a form you resubmit.