Bond Price & Yield Calculator
Price a fixed-income bond from its coupon, maturity and the market yield. See whether it trades at a premium, discount or par, plus current yield, total coupon income and modified duration — how much its price moves when rates change.
How it works
A bond is just a stream of future cash flows: a fixed coupon paid every period, plus the face (par) value returned at maturity. Its fair price is the present value of those cash flows, discounted at the market yield investors currently demand for similar risk.
For each period we use the per-period coupon c = face × (coupon rate / frequency) and the per-period yield y = market yield / frequency over n = years × frequency periods:
The first term values all the coupons; the second discounts the return of par. If the yield is 0%, the price is simply every coupon plus par,
c × n + face.
The price moves inversely to yield. Because the coupon is locked in, a bond can only stay competitive by adjusting its price: when required yields rise, the price falls; when yields fall, the price rises. Current yield — annual coupon divided by price — is a quick income gauge but ignores the gain or loss back to par at maturity, which is why yield to maturity (the market yield you enter here) is the fuller measure.
Modified duration turns this sensitivity into a number. It is the Macaulay duration (the cash-flow-weighted average time to repayment) divided by (1 + y), and it estimates the percentage price change for a 1-percentage-point move in yield. Longer maturities and lower coupons push duration higher, meaning bigger price swings as rates move.