Simple Interest Calculator — Interest & Total (P×R×T)

The honest flat-interest math: principal × rate × years — loans, notes and short-term deals in one second.

Quick answer: Free simple interest calculator: P × R × T computed instantly with total amount — plus when simple beats compound.

Amount ($) Annual rate % Years

How to use

…

About this tool

Simple (flat) interest is what car dealers, personal notes and many short loans actually use — NOT the compound math most calculators assume. This one uses the exact simple formula and shows total payable.

FAQ

Simple vs compound?

Simple pays interest only on the principal; compound pays on interest too — simple is cheaper for borrowers.

Rate per year?

Yes — enter annual %; the tool handles fractional years too.

Months instead of years?

Enter years as decimals (18 months = 1.5).

Where is simple interest used?

Auto loans, personal IOUs, bonds coupons, short-term notes.

Currency?

Any.

Why is my bank charging more?

Their quote may be compound or add fees — ask for the APR breakdown; compute simple here for comparison.

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Simple Interest Calculator — Interest & Total (P×R×T)

How to use

About this tool

FAQ

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