📈 Compound Interest

$1,000 at 10% for 30 Years

Investing $1,000 at 10% annual compound interest for 30 years grows to $17,449. That's $16,449 earned in interest on top of your original $1,000.

If you want to adjust the return assumption, extend the timeframe, or add regular contributions, use the compound interest calculator.

If you want the plain-English explanation behind the numbers, read our guide to compound interest.

Compound Interest Calculator
Australia 2026
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%
$
Total value after 30 years
$17,449
Amount invested$1,000
Interest earned$16,449
Interest multiplier17.45×
Year-by-year growth
YearBalanceInterest
Yr 1$1,100+$100
Yr 2$1,210+$110
Yr 3$1,331+$121
Yr 4$1,464+$133
Yr 5$1,611+$146
Yr 6$1,772+$161
Yr 7$1,949+$177
Yr 8$2,144+$195
Yr 9$2,358+$214
Yr 10$2,594+$236
Yr 11$2,853+$259
Yr 12$3,138+$285
Yr 13$3,452+$314
Yr 14$3,797+$345
Yr 15$4,177+$380
Yr 16$4,595+$418
Yr 17$5,054+$459
Yr 18$5,560+$505
Yr 19$6,116+$556
Yr 20$6,727+$612
Yr 21$7,400+$673
Yr 22$8,140+$740
Yr 23$8,954+$814
Yr 24$9,850+$895
Yr 25$10,835+$985
Yr 26$11,918+$1,083
Yr 27$13,110+$1,192
Yr 28$14,421+$1,311
Yr 29$15,863+$1,442
Yr 30$17,449+$1,586
Final balance after 30 years
$17,449
Invested
$1,000
Interest earned
$16,449
Multiplier
17.45×

How $1,000 grows at 10%

Compound interest earns returns on your returns — not just your original investment. At 10% per year, your money doubles every 7.2 years (the Rule of 72). Over 30 years, that compounds to a 17.45× multiplier.

In year 1, $1,000 earns $100 in interest. By year 30, the annual interest has grown to $1,586 — because each year's interest is calculated on a larger balance.

This is why longer holding periods matter so much. The later years do more of the heavy lifting, especially once the balance is large enough to generate bigger dollar returns each year.

$1,000 for 30 years at different rates
RateFinal balanceInterest earnedMultiplier
4%$3,243$2,2433.24×
5%$4,322$3,3224.32×
6%$5,743$4,7435.74×
7%$7,612$6,6127.61×
8%$10,063$9,06310.06×
9%$13,268$12,26813.27×
10% ◀$17,449$16,44917.45×

Year-by-year projection

YearBalanceInterest this yearTotal interestGrowth
Year 1$1,100+$100$1001.10×
Year 2$1,210+$110$2101.21×
Year 3$1,331+$121$3311.33×
Year 4$1,464+$133$4641.46×
Year 5$1,611+$146$6111.61×
Year 6$1,772+$161$7721.77×
Year 7$1,949+$177$9491.95×
Year 8$2,144+$195$1,1442.14×
Year 9$2,358+$214$1,3582.36×
Year 10$2,594+$236$1,5942.59×
Year 11$2,853+$259$1,8532.85×
Year 12$3,138+$285$2,1383.14×
Year 13$3,452+$314$2,4523.45×
Year 14$3,797+$345$2,7973.80×
Year 15$4,177+$380$3,1774.18×
Year 16$4,595+$418$3,5954.59×
Year 17$5,054+$459$4,0545.05×
Year 18$5,560+$505$4,5605.56×
Year 19$6,116+$556$5,1166.12×
Year 20$6,727+$612$5,7276.73×
Year 21$7,400+$673$6,4007.40×
Year 22$8,140+$740$7,1408.14×
Year 23$8,954+$814$7,9548.95×
Year 24$9,850+$895$8,8509.85×
Year 25$10,835+$985$9,83510.83×
Year 26$11,918+$1,083$10,91811.92×
Year 27$13,110+$1,192$12,11013.11×
Year 28$14,421+$1,311$13,42114.42×
Year 29$15,863+$1,442$14,86315.86×
Year 30$17,449+$1,586$16,44917.45×

Growth chart

Balance growth over 30 years
$4k$9k$13k$17kYr1Yr5Yr10Yr15Yr20Yr25Yr30
Principal
Interest earned

Frequently asked questions

Related compound interest scenarios

Use these nearby examples to compare what changes when you keep the same starting balance, extend the investing period, or test a more aggressive return assumption.

Compound interest guide and tools

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