Compound Interest Calculator — Savings Growth & Goals
Project compound interest with monthly contributions, compare APR and APY, adjust for inflation, or calculate the monthly savings needed for a goal.
Savings growth over time
Projection details
| Initial balance | |
| Added after start | |
| Interest earned | |
| Nominal ending value | |
| Inflation adjustment | |
| Effective monthly rate |
Year-by-year schedule
| Year | Starting balance | Contributed | Interest | Ending balance |
|---|
Compound interest calculator with monthly contributions
Project a starting balance plus recurring monthly deposits. Choose contribution timing, model annual increases, and separate your own contributions from compound interest.
Savings goal calculator
Goal mode solves for the monthly amount needed to reach a target by a selected date. If current savings already fund the target, the required contribution is zero.
APY vs. APR
APY is an effective annual yield that already includes compounding. A nominal APR needs a compounding frequency; this calculator converts either rate to an equivalent monthly growth rate.
Inflation-adjusted savings
The today's-money estimate discounts the future balance by the entered inflation rate. It helps compare future purchasing power, but inflation and investment returns are uncertain.
Compound interest formula
Without contributions, future value is P × (1 + r/n)ⁿᵗ for nominal APR, where P is principal, r is the annual rate, n is compounding periods per year, and t is years. Recurring deposits are simulated monthly.
Important assumptions
Results are estimates before taxes, fees, account limits, and changing rates. Investment returns are not guaranteed, and bank APYs can change. Confirm product terms before making a decision.
Sources
Investor.gov compound interest calculatorCFPB compound interest guideInvestor.gov definition
