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Financial Calculators● INSTANT WASM ENGINE
Investment Compound Interest & ROI Calculator
Model future investment portfolios with periodic contributions, compound interest cycles, and inflation considerations.
Input Parameters
$
$
8 %
1 %30 %
20 Years
1 Years50 Years
Future Portfolio Value Instant
$343,778
Growth over 20 years at 8% return
Proportional Breakdown100% Total
Total Contributions:$130,000
Compound Returns:$213,778
Analytical Summary
Total Invested Capital$130,000
Total Compound Growth$213,778
Initial Deposit$10,000
Periodic Contributions$120,000
Mathematical Formula & Methodology
Underlying equations and mathematical logic governing this engine
Step 01
Compound Interest on Initial Principal
FV_initial = P * (1 + r/n)^(n*t)Calculate appreciation on lump-sum principal.
Step 02
Future Value of Annuity Stream
FV_annuity = PMT * [((1 + r/n)^(n*t) - 1) / (r/n)]Accumulate periodic recurring deposits.
Step 03
Total Portfolio Valuation
Total = FV_initial + FV_annuitySum combined compound assets at terminal date.
How to Use This Calculator
1
Set Starting Balance
Enter current portfolio valuation or seed deposit.
2
Define Monthly Savings Rate
Determine ongoing contributions added at the end of each period.
3
Select Annualized Return Target
S&P 500 historically averages ~7-10% long-term annualized returns.