Interest Calculator

Calculate simple and compound interest

Interest Type

Principal ($)

Annual Interest Rate (%)

Time (years)

Result

Enter values and click Calculate to see results.

Financial

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Written by the EachTools Team

Last updated: January 2026

How Interest Calculations Work

This calculator handles both simple and compound interest. Simple interest is calculated only on the principal, while compound interest includes previously earned interest.

Formula

Simple: I = P × r × t
Compound: A = P(1 + r/n)^(nt)

Steps

Choose between simple or compound interest.
Enter the principal amount.
Input the annual interest rate.
Enter the time period.
View total interest earned and final balance.

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