📈 Compound Interest
$100,000 at 5% for 20 Years
Investing $100,000 at 5% annual compound interest for 20 years grows to $265,330. That's $165,330 earned in interest on top of your original $100,000.
Compound Interest Calculator
Australia 2026
$
%
$
Total value after 20 years
$265,330
Amount invested$100,000
Interest earned$165,330
Interest multiplier2.65×
Year-by-year growth
| Year | Balance | Interest |
|---|---|---|
| Yr 1 | $105,000 | +$5,000 |
| Yr 2 | $110,250 | +$5,250 |
| Yr 3 | $115,763 | +$5,513 |
| Yr 4 | $121,551 | +$5,788 |
| Yr 5 | $127,628 | +$6,078 |
| Yr 6 | $134,010 | +$6,381 |
| Yr 7 | $140,710 | +$6,700 |
| Yr 8 | $147,746 | +$7,036 |
| Yr 9 | $155,133 | +$7,387 |
| Yr 10 | $162,889 | +$7,757 |
| Yr 11 | $171,034 | +$8,144 |
| Yr 12 | $179,586 | +$8,552 |
| Yr 13 | $188,565 | +$8,979 |
| Yr 14 | $197,993 | +$9,428 |
| Yr 15 | $207,893 | +$9,900 |
| Yr 16 | $218,287 | +$10,395 |
| Yr 17 | $229,202 | +$10,914 |
| Yr 18 | $240,662 | +$11,460 |
| Yr 19 | $252,695 | +$12,033 |
| Yr 20 | $265,330 | +$12,635 |
Final balance after 20 years
$265,330
Invested
$100,000
Interest earned
$165,330
Multiplier
2.65×
How $100,000 grows at 5%
Compound interest earns returns on your returns — not just your original investment. At 5% per year, your money doubles every 14.4 years (the Rule of 72). Over 20 years, that compounds to a 2.65× multiplier.
In year 1, $100,000 earns $5,000 in interest. By year 20, the annual interest has grown to $12,635 — because each year's interest is calculated on a larger balance.
Year-by-year projection
| Year | Balance | Interest this year | Total interest | Growth |
|---|---|---|---|---|
| Year 1 | $105,000 | +$5,000 | $5,000 | 1.05× |
| Year 2 | $110,250 | +$5,250 | $10,250 | 1.10× |
| Year 3 | $115,763 | +$5,513 | $15,763 | 1.16× |
| Year 4 | $121,551 | +$5,788 | $21,551 | 1.22× |
| Year 5 | $127,628 | +$6,078 | $27,628 | 1.28× |
| Year 6 | $134,010 | +$6,381 | $34,010 | 1.34× |
| Year 7 | $140,710 | +$6,700 | $40,710 | 1.41× |
| Year 8 | $147,746 | +$7,036 | $47,746 | 1.48× |
| Year 9 | $155,133 | +$7,387 | $55,133 | 1.55× |
| Year 10 | $162,889 | +$7,757 | $62,889 | 1.63× |
| Year 11 | $171,034 | +$8,144 | $71,034 | 1.71× |
| Year 12 | $179,586 | +$8,552 | $79,586 | 1.80× |
| Year 13 | $188,565 | +$8,979 | $88,565 | 1.89× |
| Year 14 | $197,993 | +$9,428 | $97,993 | 1.98× |
| Year 15 | $207,893 | +$9,900 | $107,893 | 2.08× |
| Year 16 | $218,287 | +$10,395 | $118,287 | 2.18× |
| Year 17 | $229,202 | +$10,914 | $129,202 | 2.29× |
| Year 18 | $240,662 | +$11,460 | $140,662 | 2.41× |
| Year 19 | $252,695 | +$12,033 | $152,695 | 2.53× |
| Year 20 | $265,330 | +$12,635 | $165,330 | 2.65× |
Growth chart
Balance growth over 20 years
Principal
Interest earned
Frequently asked questions
Explore other scenarios
$100,000 for 20 years — other rates
$100,000 at 5% — other time horizons
Related calculators
Compound Interest Calculator
Australia 2026
$
%
$
Total value after 20 years
$265,330
Amount invested$100,000
Interest earned$165,330
Interest multiplier2.65×
Year-by-year growth
| Year | Balance | Interest |
|---|---|---|
| Yr 1 | $105,000 | +$5,000 |
| Yr 2 | $110,250 | +$5,250 |
| Yr 3 | $115,763 | +$5,513 |
| Yr 4 | $121,551 | +$5,788 |
| Yr 5 | $127,628 | +$6,078 |
| Yr 6 | $134,010 | +$6,381 |
| Yr 7 | $140,710 | +$6,700 |
| Yr 8 | $147,746 | +$7,036 |
| Yr 9 | $155,133 | +$7,387 |
| Yr 10 | $162,889 | +$7,757 |
| Yr 11 | $171,034 | +$8,144 |
| Yr 12 | $179,586 | +$8,552 |
| Yr 13 | $188,565 | +$8,979 |
| Yr 14 | $197,993 | +$9,428 |
| Yr 15 | $207,893 | +$9,900 |
| Yr 16 | $218,287 | +$10,395 |
| Yr 17 | $229,202 | +$10,914 |
| Yr 18 | $240,662 | +$11,460 |
| Yr 19 | $252,695 | +$12,033 |
| Yr 20 | $265,330 | +$12,635 |