◆ CALCULATOR
Compound Interest
See exactly how your money grows over time, and why starting early matters more than the amount.
Try an example
Final Balance
$326,582
Total Contributed
$82,000
Interest Earned
$244,582
Return Multiple
3.98x
Total ContributedBalance
| x | Total Contributed | Balance |
|---|---|---|
| Yr 1 | $12,400 | $13,216 |
| Yr 2 | $14,800 | $16,664 |
| Yr 3 | $17,200 | $20,362 |
| Yr 4 | $19,600 | $24,327 |
| Yr 5 | $22,000 | $28,578 |
| Yr 6 | $24,400 | $33,137 |
| Yr 7 | $26,800 | $38,026 |
| Yr 8 | $29,200 | $43,268 |
| Yr 9 | $31,600 | $48,888 |
| Yr 10 | $34,000 | $54,916 |
| Yr 11 | $36,400 | $61,378 |
| Yr 12 | $38,800 | $68,308 |
| Yr 13 | $41,200 | $75,739 |
| Yr 14 | $43,600 | $83,708 |
| Yr 15 | $46,000 | $92,252 |
| Yr 16 | $48,400 | $101,414 |
| Yr 17 | $50,800 | $111,238 |
| Yr 18 | $53,200 | $121,772 |
| Yr 19 | $55,600 | $133,068 |
| Yr 20 | $58,000 | $145,180 |
| Yr 21 | $60,400 | $158,169 |
| Yr 22 | $62,800 | $172,096 |
| Yr 23 | $65,200 | $187,029 |
| Yr 24 | $67,600 | $203,043 |
| Yr 25 | $70,000 | $220,214 |
| Yr 26 | $72,400 | $238,626 |
| Yr 27 | $74,800 | $258,369 |
| Yr 28 | $77,200 | $279,540 |
| Yr 29 | $79,600 | $302,241 |
| Yr 30 | $82,000 | $326,582 |
How to use this calculator
- Enter your starting balanceWhat you've already saved or invested today.
- Add your monthly contribution and expected returnUse a long-run figure, about 7% is common for a diversified stock portfolio.
- Set the time horizonThe longer the timeline, the more of the result comes from compounding rather than your deposits.
Compound interest is interest earning interest: each period's gains fold back into your balance, so the base you earn on keeps growing. Over a long enough horizon, time does far more of the work than the amount you save.
◆ Frequently Asked Questions
What rate of return should I use?
For a diversified stock portfolio, a long-run figure of about 7% per year after inflation is common. If your money is mostly in bonds or cash, use a lower rate, since those earn less.
Why does starting early matter more than saving more?
Compounding pays interest on your past interest, so the earliest dollars have the most time to grow. A smaller amount invested in your twenties often beats a larger amount started in your forties.
Does this result account for inflation?
No. The total is in future dollars. To see today's buying power instead, use a return rate that already subtracts inflation, for example 7% rather than a 10% nominal figure.
Keep reading
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What Is a Dividend?
Payments made by companies to shareholders, usually from earnings. A key component of stock returns.
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Spreading investments across different assets to reduce risk. The principle of 'not putting all eggs in one basket.'
◆ INVESTING BASICS
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