Compound Interest Calculator
Enter your starting amount, an optional monthly contribution, the annual interest rate and how long you'll invest, and see how compounding grows your money each year.
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| Year | Contributed | Interest | Balance |
|---|---|---|---|
1 | $10,000.00 | $722.90 | $10,722.90 |
2 | $10,000.00 | $1,498.06 | $11,498.06 |
3 | $10,000.00 | $2,329.26 | $12,329.26 |
4 | $10,000.00 | $3,220.54 | $13,220.54 |
5 | $10,000.00 | $4,176.25 | $14,176.25 |
6 | $10,000.00 | $5,201.06 | $15,201.06 |
7 | $10,000.00 | $6,299.94 | $16,299.94 |
8 | $10,000.00 | $7,478.26 | $17,478.26 |
9 | $10,000.00 | $8,741.77 | $18,741.77 |
10 | $10,000.00 | $10,096.61 | $20,096.61 |
This tool is for informational and estimation purposes only; it does not constitute legal, financial, or tax advice. Results may change based on current regulations; for exact, binding calculations, consult the relevant official authority, accountant, or lawyer.
How to Use
- 1Enter the starting amount and, optionally, how much you'll add every month.
- 2Enter the expected annual interest rate and the number of years.
- 3Choose how often interest compounds: yearly, quarterly, monthly or daily.
- 4Read the final balance and the year-by-year table, which splits your contributions from the interest earned.
Frequently Asked Questions
What is compound interest?
Compound interest is interest earned on your interest. Each period's interest is added to the balance, so the next period's interest is calculated on a larger amount. Over long periods, this makes growth speed up.
Does compounding frequency matter much?
More frequent compounding gives slightly more, but the difference between monthly and daily is small. The interest rate, how much you add, and how long you stay invested matter far more.
Are taxes and inflation included?
No. The result is a nominal, pre-tax figure. Real returns depend on taxes, fees and inflation, and investment returns aren't guaranteed. This tool is for illustration, not financial advice.