Compound Interest Calculator
See how your savings grow. Add regular deposits and see the end balance, the interest and the APY.
- Free. No sign-up.
- No limits per day.
- Your numbers stay on your device.
- One page does one job.
A whole number from 1 to 100.
Use it for a yearly raise. The deposit grows at the start of each year.
Above 0, the result also shows the balance in today's money.
The currency changes the symbol only. The calculator does not convert money.
End balance
$37,405.09
| Total deposits | $22,000.00 |
|---|---|
| Total interest | $15,405.09 |
| Effective annual rate (APY) | 7.229% |
| Money doubles in about | 9.9 years |
The rule of 72 is a quick estimate: 72 divided by the rate gives 10.3 years.
After 10 years: deposits so far $22,000.00, interest so far $15,405.09, balance $37,405.09.
- Deposits so far
- Interest so far
Yearly schedule
| Year | Deposits that year | Interest that year | Total deposits | Total interest | Balance |
|---|---|---|---|---|---|
| 1 | $1,200.00 | $762.16 | $11,200.00 | $762.16 | $11,962.16 |
| 2 | $1,200.00 | $904.00 | $12,400.00 | $1,666.16 | $14,066.16 |
| 3 | $1,200.00 | $1,056.10 | $13,600.00 | $2,722.27 | $16,322.27 |
| 4 | $1,200.00 | $1,219.20 | $14,800.00 | $3,941.46 | $18,741.46 |
| 5 | $1,200.00 | $1,394.08 | $16,000.00 | $5,335.54 | $21,335.54 |
| 6 | $1,200.00 | $1,581.61 | $17,200.00 | $6,917.15 | $24,117.15 |
| 7 | $1,200.00 | $1,782.69 | $18,400.00 | $8,699.84 | $27,099.84 |
| 8 | $1,200.00 | $1,998.31 | $19,600.00 | $10,698.15 | $30,298.15 |
| 9 | $1,200.00 | $2,229.51 | $20,800.00 | $12,927.66 | $33,727.66 |
| 10 | $1,200.00 | $2,477.43 | $22,000.00 | $15,405.09 | $37,405.09 |
Sources: SEC Investor.gov, CFPB and the Financial Consumer Agency of Canada. Checked on 2026-11-11. See how the numbers work.
Questions
What is compound interest?
Compound interest is interest on your money and on the interest you already earned. For example, $10,000.00 at 5% a year grows to $16,288.95 in 10 years. Simple interest gives only $15,000.00.
How does the compounding frequency change the result?
More frequent compounding gives a little more money. Take $10,000.00 at 5% for 10 years. Yearly compounding gives $16,288.95. Monthly gives $16,470.09. Daily gives $16,486.65.
Is it better to deposit at the start or at the end of a period?
A deposit at the start earns interest for one more period. Take $100.00 a month at 7% for 10 years, with no starting amount. Deposits at the end give $17,308.48. Deposits at the start give $17,409.45.
What is APY?
APY is the annual percentage yield. It is the real yearly rate after compounding. A rate of 5% compounded monthly has an APY of 5.116%. Use APY to compare accounts.
What is the rule of 72?
The rule of 72 is a quick estimate. Divide 72 by the yearly rate to get the years to double your money. At 6%, 72 divided by 6 is 12 years. The exact value is 11.9 years.