Free tool
Compound interest calculator
Enter a starting balance, a yearly rate, the years and any regular contribution to see the ending balance and the interest earned.
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How it works
How it works
Each period the balance earns rate divided by periods per year. The ending balance is the starting amount grown by compounding, plus each contribution grown from the period it was added. Contributions are assumed to be made at the end of each period.
FAQ
About this calculator
What is compound interest?
Interest earned on both the original amount and the interest already added. Over time it grows faster than simple interest.
Is the rate guaranteed?
No. Savings and investment returns vary. The calculator shows what a steady rate would produce, not what you will earn.
What does the compounding frequency change?
More frequent compounding adds interest to the balance sooner, so the ending balance is slightly higher at the same yearly rate.
Is anything saved?
No. The math runs in your browser and nothing you enter is sent to us.
Is this tax or financial advice?
No. It is a calculator for general information. Check the numbers against your own records, and ask an accountant before you act on them.
Read the guide: How to Track Your Net Worth (and Why It Matters). Related: simple interest calculator, business loan payment calculator. See all free tools. More free tools: MCC Tax 1040 software, Real estate commission split calculator, HOA dues per unit calculator, or see all free tools.
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