How This Calculator Works & Financial Methodology
Banks advertise headline nominal APY or annual profit rates, but withholding tax (such as 15% Filer vs. 30% Non-Filer or marginal income tax) and CPI inflation significantly reduce real purchasing power. This model computes exact monthly payout, net maturity value after tax, and inflation-adjusted real return.
Real After-Tax Fixed Income Formula
Net Real Yield = [(1 + Gross Rate × (1 − Tax Rate)) / (1 + Inflation Rate)] − 1