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Finance
Compound Interest Calculator
Project future value with compounding frequency and optional contributions. Free, no signup, works worldwide.
Inputs
Initial amount
Uses same period as compounding frequency
Results
Future value
—
Total contributed—
Interest earned—
Growth on starting principal—
Assumptions—
Results update when you click Calculate. Currency formatting follows your selected code.
How this calculator works
Combines initial investment principal, regular recurring deposits, interest rate, compounding frequency, and duration to calculate final portfolio growth over time.
Formula
A = P × (1 + r/n)^(nt) + PMT × [((1 + r/n)^(nt) - 1) / (r/n)]
Worked Example
Initial deposit of $10,000 with monthly additions of $200 at an 7% annual interest rate compounded monthly for 10 years results in $53,741 final balance ($34,000 total contributions + $19,741 total interest earned).
Assumptions
- Interest rate remains constant throughout the investment period.
- Recurring contributions occur at the end of each compounding period.
- All earned interest is reinvested without intermediate withdrawals.
Limitations
- Excludes capital gains taxes, dividend tax obligations, and fund management fees.
- Does not account for inflation or purchasing power erosion over long horizons.
Related reading
Disclaimer: Educational estimate only. Not financial, tax, insurance, or legal advice. Verify with a local professional. See our Disclaimer.