Compound Interest Calculator
Work out how much an amount grows with compound interest, the effective yearly rate, and a table of the balance year by year.
Compound interest
Type the amount, the rate, the years and how often interest is added.
Final amount
1,647.01
647.01
Interest earned
5.1162%
Effective yearly rate
Year by year
| Year | Interest earned that year | Balance at year end |
|---|---|---|
| 1 | 51.16 | 1,051.16 |
| 2 | 53.78 | 1,104.94 |
| 3 | 56.53 | 1,161.47 |
| 4 | 59.42 | 1,220.90 |
| 5 | 62.46 | 1,283.36 |
| 6 | 65.66 | 1,349.02 |
| 7 | 69.02 | 1,418.04 |
| 8 | 72.55 | 1,490.59 |
| 9 | 76.26 | 1,566.85 |
| 10 | 80.16 | 1,647.01 |
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On this page
Compound interest examples
| 1,000 at 5% for 10 years | Final amount |
|---|---|
| once a year | 1,628.89 |
| twice a year | 1,638.62 |
| every quarter | 1,643.62 |
| every month | 1,647.01 |
| every day | 1,648.66 |
| continuously | 1,648.72 |
Formula
A = P x (1 + r / m)^(m x t); continuous: A = P x e^(r x t)
P = starting amount, r = yearly rate as a fraction, m = times interest is added per year, t = years. The effective yearly rate is (1 + r / m)^m - 1.
How the compound interest works
- Step oneType the starting amount, the yearly rate and the number of years.
- Step twoChoose how often the interest is added.
- Step threeRead the final amount, the interest and the year-by-year table.
What this tool does not do
- It does not add regular deposits or withdrawals.
- It assumes a fixed rate for the whole time and ignores taxes, fees and inflation.
- It is an illustration of the maths, not a forecast or financial advice.
Frequently asked questions
Why does adding interest more often give more?
Each addition earns interest on the interest before it. The gain is small: at 5%, monthly gives 1,647.01 on 1,000 over 10 years, and daily gives 1,648.66.
What is the effective yearly rate?
The single yearly rate that gives the same result as the chosen rate with its adding schedule. It is also called APY.
Does it add regular deposits?
No. It works on one starting amount. Regular deposits, taxes and fees are not modeled.