Finance
Simple Interest Calculator
Quick simple-interest math on any principal, rate and term.
How this simple interest calculator works
The simple interest calculator takes the numbers you enter and applies a standard formula for this kind of calculation, showing the result instantly with no page reload. Quick simple-interest math on any principal, rate and term.
Everything runs client-side in JavaScript, so your inputs never leave your device — there's no server, no account and no tracking involved in getting your answer.
Frequently asked questions
Simple interest is calculated only on the original principal for the entire term. Compound interest is calculated on the principal plus any interest already earned, so it grows faster over time.