Compound Interest Calculator
Compound Interest Calculator: free, accurate and easy to use. Results update instantly in your browser, with no sign-up.
How to use
See how savings or investments can grow with compound interest, where you earn interest on both your original amount and on previous interest. Enter a starting amount, optional monthly contributions, the annual rate and the number of years. Results are projections, not guarantees.
- Enter your numbers.
- Results update instantly as you type.
- Adjust the values to compare scenarios.
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Frequently asked questions
What is the compound interest formula?
A = P(1 + r/n)^(nt), where P is the principal, r the annual rate, n the compounding periods per year and t the number of years.
Are returns guaranteed?
No. Real returns vary, and this calculator assumes a constant rate for illustration only.
Is it free?
Yes. All calculators are free, with no sign-up and no limits.
Is my data stored?
No. Calculations run in your browser and nothing you enter is sent or stored.
How accurate are the results?
Calculations use standard formulas. Results are estimates for general information; for important decisions, confirm with a professional or your provider.