Interest Calculator

Calculate simple interest: enter principal, annual rate and time in years.

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Simple Interest Formula

Interest = Principal × Rate × Time

Total = Principal + Interest

Example

$5,000 at 4% annual interest for 3 years:

  • Interest = 5000 × 0.04 × 3 = $600
  • Total = $5,600

Frequently Asked Questions

Multiply principal × annual rate × years. $5,000 at 4% for 3 years earns 5000 × 0.04 × 3 = $600.

Simple interest is paid only on the principal. Compound interest is also paid on accumulated interest, so it grows faster.

Yes — many auto loans, short-term personal loans and bonds use simple interest. Mortgages and credit cards typically compound.

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