🧮 Financial Tool
Compound Interest Calculator
See how your money grows over time with compound interest, monthly contributions, and multiple solve modes.
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💰 Final Amount
$300,851
💵 Total Contributed
$130,000
📈 Interest Earned
$170,851
131.4% on contributions
Growth Projection
Your calculation step by step
A = P × (1 + r/n)n×t + PMT × [(1+r/n)^(n×t) - 1] / (r/n)
P = $10,000
r = 7%
n = 12
t = 20 years
PMT = $500/mo
A = $300,851
| Year | Balance | Contributed | Interest |
|---|---|---|---|
| 1 | $16,919 | $16,000 | $919 |
| 2 | $24,339 | $22,000 | $2,339 |
| 3 | $32,294 | $28,000 | $4,294 |
| 4 | $40,825 | $34,000 | $6,825 |
| 5 | $49,973 | $40,000 | $9,973 |
| 6 | $59,782 | $46,000 | $13,782 |
| 7 | $70,299 | $52,000 | $18,299 |
| 8 | $81,578 | $58,000 | $23,578 |
| 9 | $93,671 | $64,000 | $29,671 |
| 10 | $106,639 | $70,000 | $36,639 |
| 11 | $120,544 | $76,000 | $44,544 |
| 12 | $135,455 | $82,000 | $53,455 |
| 13 | $151,443 | $88,000 | $63,443 |
| 14 | $168,587 | $94,000 | $74,587 |
| 15 | $186,971 | $100,000 | $86,971 |
| 16 | $206,683 | $106,000 | $100,683 |
| 17 | $227,820 | $112,000 | $115,820 |
| 18 | $250,486 | $118,000 | $132,486 |
| 19 | $274,790 | $124,000 | $150,790 |
| 20 | $300,851 | $130,000 | $170,851 |
Methodology
A = P × (1 + r/n)^(n×t) + PMT × [(1+r/n)^(n×t) - 1] / (r/n)
P = initial principal, r = annual rate, n = compounds per year, t = years, PMT = periodic contribution. Compound interest reinvests gains, creating exponential growth over time.
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