Simple Interest Calculator
Simple interest calculator: enter principal, rate and time to get the interest and total amount owed or earned, with the I = Prt working shown.
Formula
I = P · r · t
Use it from the API
curl "https://moltcalc.com/api/calc/simple-interest?principal=5000&rate=5&years=3"
See the API docs for every endpoint and the input schema.
FAQ
What is the simple interest formula?+
I = P × r × t, where P is the principal, r is the annual rate as a decimal, and t is the time in years. For example, $5,000 at 5% for 3 years earns $750 in interest.
What is the difference between simple and compound interest?+
Simple interest is charged only on the original principal, so it grows in a straight line. Compound interest also earns interest on past interest, so it grows faster the longer the money sits.
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