The everyday toolkit
Interest Calculator
Compare simple and compound interest with annual, quarterly, monthly or daily compounding.
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Your result
A clear answer starts here.
Enter your values and choose Calculate to see the result. Changing a value clears the previous answer.
Results are rounded to two decimal places for display. Calculations use unrounded values. Use the same currency for all monetary inputs.
How this calculator works
Assumes a constant nominal annual rate with no additional deposits, withdrawals, fees or taxes. Fractional years are allowed and compound growth is modeled over that period.
Simple: interest = P × r × t. Compound: final amount = P × (1 + r ÷ n)ⁿᵗ, where n is the number of compounding periods per year.