About the Simple Interest Calculator
Compute simple interest (I = P × r × t) from principal, rate and time, with total amount and formula steps shown. A comparison line shows what compound interest would yield for context.
Simple interest applies to many personal loans, auto loans and short-term deposits.
How to use the Simple Interest Calculator
- Enter principal, annual rate and time period.
- Read the interest and final amount with steps.
- Compare against the compound interest line.
Common uses
Auto and personal loan interest
Short-term deposit returns
Finance homework
Frequently asked questions
Simple vs compound interest?
Simple interest is charged only on the principal; compound interest also accrues on accumulated interest, growing faster over time.
What formula is used?
I = P × r × t, where r is the annual rate as a decimal and t is time in years.
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