Related tool
Simple Interest Calculator
Estimate how much interest a fixed principal earns over time at a simple (non-compounding) rate.
Simple interest is calculated only on the original principal, unlike compound interest, which also earns interest on previously accumulated interest. The formula is straightforward: interest equals principal multiplied by the annual rate multiplied by the number of years, all divided by 100.
For example, $5135 at 4% simple interest over 2 years earns $410.8 in interest, for a total value of $5545.8. This is a common way to estimate short-term savings products, certain personal loans, and back-of-envelope comparisons where compounding is not part of the agreement.
If your product compounds interest monthly, quarterly, or annually, the result will differ from this simple-interest figure — usually by a small amount over short periods, but by a larger amount the longer the money sits.
A quick tip before you start
This calculator updates the instant you change a field, the same as every other one on QuickWallet, so there is no submit button to wait on and nothing leaves your browser. If a number looks wrong, check the units first — a mismatched unit causes far more surprises than an actual formula bug.
If this is the calculation you reach for most, bookmark this page specifically rather than the homepage — it lives at its own address, so you land here directly next time instead of clicking through.