Finance · Flat rate

Simple interest calculator

Interest calculated only on the original principal — no compounding.

Details

Total amount
—
Principal plus simple interest
Interest earned—

Rough sheet

step-by-step
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How simple interest is calculated

Simple interest is calculated only on the original principal for the entire term, using the formula Interest = Principal × Rate × Time — unlike compound interest, previously earned interest never itself earns further interest. That makes simple interest easier to predict but slower-growing over long periods than an equivalent compound-interest account at the same rate.

Frequently asked questions

Simple interest is calculated only on the original principal for the whole term, while compound interest also earns interest on previously accumulated interest.

Interest = Principal × Rate × Time, added to the principal for your total.