Compound Interest Calculator
Enter principal, annual interest rate, term in years, and compounding frequency (daily, weekly, monthly, quarterly, semi-annual, or annual). Instantly see future value, total interest earned, and total return percentage, plus a year-by-year growth table. Pure math only — not financial advice. Runs in your browser.
Estimate future value and total interest for a principal amount using a fixed annual rate, investment duration, and selectable compounding frequency.
How to calculate compound interest
- Enter the starting principal, annual interest rate, and number of years.
- Choose annual, semiannual, quarterly, monthly, weekly, or daily compounding.
- Calculate to see future value, total interest, total return, and a year-by-year schedule.
How the calculation works
The calculator uses A = P(1 + r/n)^(nt), where n is the selected number of compounding periods per year.
The schedule is capped at 50 displayed years and calculates each displayed year independently from the original principal and fixed rate.
Privacy and limitations
The calculation is browser-local and does not contact a bank or investment service. It assumes a constant rate, no additional deposits or withdrawals, no taxes or fees, and no changing compounding rules.
Compound Interest Calculator FAQ
Which compounding periods are supported?
Annual, semiannual, quarterly, monthly, weekly, and daily.
Does it support recurring contributions?
No. It uses one starting principal only.
Can the interest rate change over time?
No. One fixed annual rate is used.
How many years are shown in the schedule?
Up to 50 displayed years.
Is this financial advice?
No. It is a mathematical estimate based on your inputs.