📈 Compound Interest

$5,000 at 8% for 20 Years

Investing $5,000 at 8% annual compound interest for 20 years grows to $23,305. That's $18,305 earned in interest on top of your original $5,000.

Compound Interest Calculator
Australia 2026
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%
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Total value after 20 years
$23,305
Amount invested$5,000
Interest earned$18,305
Interest multiplier4.66×
Year-by-year growth
YearBalanceInterest
Yr 1$5,400+$400
Yr 2$5,832+$432
Yr 3$6,299+$467
Yr 4$6,802+$504
Yr 5$7,347+$544
Yr 6$7,934+$588
Yr 7$8,569+$635
Yr 8$9,255+$686
Yr 9$9,995+$740
Yr 10$10,795+$800
Yr 11$11,658+$864
Yr 12$12,591+$933
Yr 13$13,598+$1,007
Yr 14$14,686+$1,088
Yr 15$15,861+$1,175
Yr 16$17,130+$1,269
Yr 17$18,500+$1,370
Yr 18$19,980+$1,480
Yr 19$21,579+$1,598
Yr 20$23,305+$1,726
Final balance after 20 years
$23,305
Invested
$5,000
Interest earned
$18,305
Multiplier
4.66×

How $5,000 grows at 8%

Compound interest earns returns on your returns — not just your original investment. At 8% per year, your money doubles every 9 years (the Rule of 72). Over 20 years, that compounds to a 4.66× multiplier.

In year 1, $5,000 earns $400 in interest. By year 20, the annual interest has grown to $1,726 — because each year's interest is calculated on a larger balance.

$5,000 for 20 years at different rates
RateFinal balanceInterest earnedMultiplier
4%$10,956$5,9562.19×
5%$13,266$8,2662.65×
6%$16,036$11,0363.21×
7%$19,348$14,3483.87×
8% ◀$23,305$18,3054.66×
9%$28,022$23,0225.60×
10%$33,637$28,6376.73×

Year-by-year projection

YearBalanceInterest this yearTotal interestGrowth
Year 1$5,400+$400$4001.08×
Year 2$5,832+$432$8321.17×
Year 3$6,299+$467$1,2991.26×
Year 4$6,802+$504$1,8021.36×
Year 5$7,347+$544$2,3471.47×
Year 6$7,934+$588$2,9341.59×
Year 7$8,569+$635$3,5691.71×
Year 8$9,255+$686$4,2551.85×
Year 9$9,995+$740$4,9952.00×
Year 10$10,795+$800$5,7952.16×
Year 11$11,658+$864$6,6582.33×
Year 12$12,591+$933$7,5912.52×
Year 13$13,598+$1,007$8,5982.72×
Year 14$14,686+$1,088$9,6862.94×
Year 15$15,861+$1,175$10,8613.17×
Year 16$17,130+$1,269$12,1303.43×
Year 17$18,500+$1,370$13,5003.70×
Year 18$19,980+$1,480$14,9804.00×
Year 19$21,579+$1,598$16,5794.32×
Year 20$23,305+$1,726$18,3054.66×

Growth chart

Balance growth over 20 years
$6k$12k$17k$23kYr1Yr5Yr10Yr15Yr20
Principal
Interest earned

Frequently asked questions

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