CalcPrincipalWhy every page shows its working
Most calculators hand you a number and ask for trust. Every calculator here prints its method instead: the formula, the conventions it uses (payments at period end, nominal rates divided by their compounding periods, balances simulated month by month where a formula would fudge), and a worked example you can check with a pencil. When a model is a simplification โ a credit card's daily interest, a retirement projection โ the page says so in words, next to the result, not in a footnote graveyard.
Your currency, your spelling
Money maths does not change with the flag, so neither do these calculators: pick $, ยฃ, โฌ, A$, C$ or โน in the header and every label and result follows. Spelling follows the same setting โ amortization becomes amortisation when the pound is selected.
Built by the CalcPrincipal team
CalcPrincipal is made by a small independent team and published under the site's name. Every figure is computed in your browser: we never receive or store the numbers you enter. Found a figure you believe is wrong? The method notes make it easy to point at the exact line โ write to us from the contact page. Correcting a number in the open is the whole idea of this site.