Calculate future value, total interest, and effective annual rate for a one-time deposit with annual, monthly, or daily compounding.
Compound interest formula
Compound interest adds each period’s interest to the balance, allowing later interest to grow on earlier interest. This calculator models one deposit with no later contributions or withdrawals. For recurring deposits, use the monthly investment calculator.
Future value = P × (1 + r ÷ n)^(n × t) Effective annual rate = (1 + r ÷ n)^n − 1
Nominal and effective rates
The nominal annual rate is divided by the number of compounding periods. More frequent compounding produces a slightly higher effective annual rate when the nominal rate is positive.
Frequently asked questions
Does this include monthly contributions?
No. It models a single starting deposit and reinvested interest.
Are taxes, fees, and inflation included?
No. The result is a mathematical fixed-rate scenario before taxes, fees, and inflation.
Is the return guaranteed?
No. The rate is an input for comparison and does not represent a quoted or guaranteed investment return.