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FINANCE

Compound Interest Calculator

Calculate future investment value with compound interest and regular monthly contributions. Choose compounding frequency and see year-by-year growth.

Compound

$20,096.61

Future Value

$10,000.00

Total Invested

$10,096.61

Interest Earned

101.0%

Total Return

Principal
Interest
YearBalanceInterest Earned
1$10,722.90$722.90
2$11,498.06$1,498.06
3$12,329.26$2,329.26
4$13,220.54$3,220.54
5$14,176.25$4,176.25
6$15,201.06$5,201.06
7$16,299.94$6,299.94
8$17,478.26$7,478.26
9$18,741.77$8,741.77
10$20,096.61$10,096.61

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Compounding Modes

0ms

Latency

100%

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Knowledge Base

Frequently Asked Questions

What is the compound interest formula?

A = P(1 + r/n)^(nt), where P = principal, r = annual interest rate (decimal), n = compounding frequency per year, t = time in years. With regular contributions, each payment also compounds over the remaining period.

How does compounding frequency affect growth?

More frequent compounding yields slightly more. $10,000 at 7% for 10 years: annual compounding = $19,672; monthly compounding = $20,097; daily = $20,137. The difference is small but grows with time and rate.

What is the rule of 72?

Divide 72 by the annual interest rate to estimate how long it takes to double your money. At 7% annual return: 72 ÷ 7 ≈ 10.3 years. At 10%: 72 ÷ 10 = 7.2 years.

How much should I save per month to reach $1 million?

At 7% annual return compounded monthly, starting from $0: saving $500/month = ~32 years; $1,000/month = ~27 years; $2,000/month = ~22 years. Starting earlier dramatically reduces the monthly amount needed.