📈 Compound Interest

$100,000 at 6% for 30 Years

Investing $100,000 at 6% annual compound interest for 30 years grows to $574,349. That's $474,349 earned in interest on top of your original $100,000.

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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%
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Total value after 30 years
$574,349
Amount invested$100,000
Interest earned$474,349
Interest multiplier5.74×
Year-by-year growth
YearBalanceInterest
Yr 1$106,000+$6,000
Yr 2$112,360+$6,360
Yr 3$119,102+$6,742
Yr 4$126,248+$7,146
Yr 5$133,823+$7,575
Yr 6$141,852+$8,029
Yr 7$150,363+$8,511
Yr 8$159,385+$9,022
Yr 9$168,948+$9,563
Yr 10$179,085+$10,137
Yr 11$189,830+$10,745
Yr 12$201,220+$11,390
Yr 13$213,293+$12,073
Yr 14$226,090+$12,798
Yr 15$239,656+$13,565
Yr 16$254,035+$14,379
Yr 17$269,277+$15,242
Yr 18$285,434+$16,157
Yr 19$302,560+$17,126
Yr 20$320,714+$18,154
Yr 21$339,956+$19,243
Yr 22$360,354+$20,397
Yr 23$381,975+$21,621
Yr 24$404,893+$22,918
Yr 25$429,187+$24,294
Yr 26$454,938+$25,751
Yr 27$482,235+$27,296
Yr 28$511,169+$28,934
Yr 29$541,839+$30,670
Yr 30$574,349+$32,510
Final balance after 30 years
$574,349
Invested
$100,000
Interest earned
$474,349
Multiplier
5.74×

How $100,000 grows at 6%

Compound interest earns returns on your returns — not just your original investment. At 6% per year, your money doubles every 12 years (the Rule of 72). Over 30 years, that compounds to a 5.74× multiplier.

In year 1, $100,000 earns $6,000 in interest. By year 30, the annual interest has grown to $32,510 — 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.

$100,000 for 30 years at different rates
RateFinal balanceInterest earnedMultiplier
4%$324,340$224,3403.24×
5%$432,194$332,1944.32×
6% ◀$574,349$474,3495.74×
7%$761,226$661,2267.61×
8%$1,006,266$906,26610.06×
9%$1,326,768$1,226,76813.27×
10%$1,744,940$1,644,94017.45×

Year-by-year projection

YearBalanceInterest this yearTotal interestGrowth
Year 1$106,000+$6,000$6,0001.06×
Year 2$112,360+$6,360$12,3601.12×
Year 3$119,102+$6,742$19,1021.19×
Year 4$126,248+$7,146$26,2481.26×
Year 5$133,823+$7,575$33,8231.34×
Year 6$141,852+$8,029$41,8521.42×
Year 7$150,363+$8,511$50,3631.50×
Year 8$159,385+$9,022$59,3851.59×
Year 9$168,948+$9,563$68,9481.69×
Year 10$179,085+$10,137$79,0851.79×
Year 11$189,830+$10,745$89,8301.90×
Year 12$201,220+$11,390$101,2202.01×
Year 13$213,293+$12,073$113,2932.13×
Year 14$226,090+$12,798$126,0902.26×
Year 15$239,656+$13,565$139,6562.40×
Year 16$254,035+$14,379$154,0352.54×
Year 17$269,277+$15,242$169,2772.69×
Year 18$285,434+$16,157$185,4342.85×
Year 19$302,560+$17,126$202,5603.03×
Year 20$320,714+$18,154$220,7143.21×
Year 21$339,956+$19,243$239,9563.40×
Year 22$360,354+$20,397$260,3543.60×
Year 23$381,975+$21,621$281,9753.82×
Year 24$404,893+$22,918$304,8934.05×
Year 25$429,187+$24,294$329,1874.29×
Year 26$454,938+$25,751$354,9384.55×
Year 27$482,235+$27,296$382,2354.82×
Year 28$511,169+$28,934$411,1695.11×
Year 29$541,839+$30,670$441,8395.42×
Year 30$574,349+$32,510$474,3495.74×

Growth chart

Balance growth over 30 years
$144k$287k$431k$574kYr1Yr5Yr10Yr15Yr20Yr25Yr30
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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