Compound Interest Calculator
See how your starting balance and regular contributions can grow with compounding.
Preparing your calculator…
MansionMath provides estimates for educational purposes. Actual loan terms, taxes, insurance, fees, investment returns, and eligibility may vary.
How this calculator works
The stated annual nominal rate and compounding frequency produce a monthly equivalent rate: (1 + annual rate ÷ frequency)^(frequency ÷ 12) − 1. Interest accrues monthly at that equivalent rate, followed by an end-of-month deposit. This convention supports monthly contributions even when compounding is annual or daily. Taxes and fees are excluded.
Use current quotes, local rates, and measured dimensions to make this estimate useful for your situation.
Frequently asked questions
How do I use the compound interest calculator?+
Enter your measurements or financial assumptions above. Results update instantly. $10,000 at 5% nominal annual interest compounded monthly, with no contributions, grows to about $16,470 after 10 years.
How accurate is this estimate?+
Estimates use the inputs you supply. Actual lender terms, fees, insurance, taxes, and eligibility vary. Compare quotes and verify local costs before committing.