Simple Interest Calculator

All tools

Calculate simple interest on a principal using the I = P·r·t formula. See interest earned, total amount and daily or monthly accrual instantly. Free.

$
%
Interest earned –
Total amount –
Principal –
Interest per month –
Interest per day –
Simple interest uses I = P × r × t with no compounding. Months are counted as 1/12 of a year and days as 1/365.
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