Enter principal, annual rate, duration, and frequency.
Finance Math Calculator
Compound Interest Calculator
Estimate compound growth, interest earned, periodic rate, and effective annual rate from principal, rate, time, and frequency.
Instant answer
Formula breakdown
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Interactive calculator
Enter your values
Use the example values or replace them with your own. Required validation happens before the calculation.
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Calculated answer
Result
Simple workflow
How to use the Compound Interest Calculator
Follow these steps to get a reliable result and understand how it was produced.
Divide the rate among compounding periods.
Apply the compound-growth exponent and subtract principal for interest.
Understanding the calculation
Compound interest adds each period’s interest to the balance, allowing later interest to grow on earlier interest.
A = P(1+r/n)^(nt)The result panel substitutes your numbers into this relationship and shows the important intermediate values.
Common uses
- Savings and investment projections
- Loan balance comparisons
- Understanding compounding frequency
Accuracy tips
- This assumes a constant rate and no deposits or withdrawals.
- More frequent compounding slightly increases the effective rate.
- Actual products may round periods or include fees and taxes.
Helpful answers
Compound Interest Calculator FAQs
Important details about formulas, inputs, limitations, and result interpretation.
What is compounding frequency?
It is how often interest is added to the balance each year.
What is effective annual rate?
It is the one-year growth rate after accounting for compounding.
Does this include recurring contributions?
No. It models one initial principal only.
Is monthly always much better than annual compounding?
The increase is usually modest and depends on the stated rate.