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Compound Savings Calculator
Contributions vs. growth over the years — with the chart that explains compounding.
結果
具体的な計算例
Ending balance$75,578
after 20 years at 4.0% (monthly compounding, deposits at month-end)
Total contributed$49,000
$1,000 start + $200 × 240 months
Growth from interest$26,578
Interest did 35% of the work. Stretch the years, not the monthly amount, and watch that share climb — time is the active ingredient.
A fixed rate for decades is a simplification: savings rates float and investments swing. Use it to compare scenarios, not to predict a balance.
| Year | Balance |
|---|---|
| 1 | $3,485 |
| 2 | $6,072 |
| 3 | $8,764 |
| 4 | $11,565 |
| 5 | $14,481 |
| 6 | $17,515 |
| 7 | $20,673 |
| 8 | $23,960 |
| 9 | $27,381 |
| 10 | $30,941 |
| 11 | $34,646 |
| 12 | $38,502 |
| 13 | $42,515 |
| 14 | $46,692 |
| 15 | $51,038 |
| 16 | $55,562 |
| 17 | $60,270 |
| 18 | $65,170 |
| 19 | $70,270 |
| 20 | $75,578 |
Monthly compounding, deposits at month-end, rate held constant — a comparison machine, not a prediction.