Estimate simple interest
Enter a starting amount, annual rate, and term to see the interest and ending balance.
Finance tool
Calculate interest on a principal amount.
Inputs
Interest earned
Enter a starting amount, annual rate, and term to see the interest and ending balance.
A few quick answers before you go.
It is principal multiplied by annual rate and time. Interest does not earn additional interest.
Straightforward explanations to help you use each tool well.
A practical guide to contributions, rates, and time.
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Read guide →Disclaimer: This tool is for general information only and does not provide financial, medical, or professional advice.