Compound Interest Calculator
Calculate compound interest with periodic contributions. See total, interest earned, and contributions. [NEW-2026-06-08]
Future Value
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Interest Earned
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Total Contributions
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Compound Interest Calculator — Free Online Tool
Calculate how your money grows with compound interest and periodic contributions. See your future value, total interest earned, and total contributions at a glance. Adjust the compounding frequency from daily to annually and add monthly contributions to model real-world savings.
How it works
Enter your initial investment, annual interest rate, number of years, compounding frequency, and optional periodic contribution. The calculator uses the compound interest formula: FV = P(1 + r/n)^(nt) + PMT × [(1 + r/n)^(nt) - 1] / (r/n). Results update instantly as you type.
When to use this
Use this tool when planning retirement savings, evaluating investment accounts, comparing CD or bond yields, or teaching financial literacy. It is also useful for loan interest comparison and college savings planning.
Important disclaimer
This calculator is for informational and educational purposes only. It does not constitute financial advice. Actual returns may vary due to taxes, fees, market conditions, and individual circumstances. Consult a qualified financial advisor before making investment decisions.
Related: Mortgage Calculator, Loan Payoff Calculator, APR Calculator, Credit Card Payoff Calculator, Percentage Calculator.
FAQ
Is this tool free to use?
Yes. The tool is free to use in your browser and does not require an account.
Do I need to install anything?
No. The tool runs in a normal modern browser, so you can use it on desktop or mobile without installing extra software.
Is my data uploaded to a server?
No. All processing happens locally in your browser. Your data never leaves your device.
Can I use this for production work?
Yes, but always verify the output before using it in production. Keep a copy of your original input.
What should I check before using the result?
Review the output for accuracy, formatting, encoding, and compatibility with your target system before deploying or committing.
Does this tool work offline?
Once the page is loaded, the tool runs entirely in your browser and does not need a network connection to function.