Simple Interest Calculator

Simple interest is principal × annual rate × years: $5,000 at 6% for 3 years accrues $900, the same $300 each year, because interest never joins the principal. It's the easiest interest to compute in your head — and the cheapest kind to owe.

Some lenders quote 'simple interest' but compute it on the full original balance for the whole term even as you pay it down (an add-on loan). That makes the effective rate much higher than quoted — compare using APR, not the sticker rate.