APY Calculator

APY = (1 + nominal rate ÷ compounds per year)^{compounds per year} − 1. This translates the entered nominal rate into one annual compounding measure. CFPB Regulation DD defines APY as the interest paid based on the rate and compounding frequency over a 365-day period.

The gross balance compounds smoothly at the entered rate. The after-tax-and-fee path applies the entered marginal tax percentage to each year’s modeled interest and subtracts the entered fee at year-end. The real balance divides that result by cumulative entered inflation. These are simplified user assumptions, not a bank disclosure, tax calculation, rate forecast, or guarantee.

Actual accounts may use daily balances, tiers, promotional periods, minimum balances, bonuses, withdrawal restrictions, different crediting rules, variable rates, and institution-specific rounding. Verify the bank’s current Truth in Savings disclosure and FDIC status.