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Finance Calculators

Simple Interest Calculator

Calculate simple interest earned on a principal amount over time, with no compounding.

%
years
Interest earned
Total amount
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About the Simple Interest Calculator

Simple interest grows at a constant rate because it's calculated only on the original principal — unlike compound interest, previously earned interest never earns additional interest.

Formula: I = P × r × t, where P is principal, r is the annual rate (as a decimal), and t is time in years.

Simple interest is common for short-term loans and some bonds, while most savings accounts and investments use compound interest instead.

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