Price a bond from its coupon, maturity and market yield, or find the yield to maturity you'd earn at a given price. Assumes you buy on a coupon date.
The bond price formula
A bond's price is the present value of its coupons plus the face value repaid at maturity, all discounted at the yield to maturity (YTM):
Price = C × (1 − (1 + y)−n) ÷ y + F ÷ (1 + y)ⁿ
F is the face value, C the coupon each period (F × coupon rate ÷ payments per year), y the YTM ÷ payments per year, and n the number of coupon periods left. YTM has no formula; Calcist finds the yield that makes this price match yours by bisection, to a tiny fraction of a cent.
Current yield = yearly coupon ÷ price
Worked example
A $1,000 bond with a 5% coupon paid twice a year ($25 every six months), 10 years to maturity, priced to yield 6%: y = 3%, n = 20, so the price is 25 × (1 − 1.03−20) ÷ 0.03 + 1,000 ÷ 1.03²⁰ = 371.94 + 553.68 = $925.61. It sells at a discount because its coupon is below the market yield. Its current yield is 50 ÷ 925.61 = 5.402%. At a 4% yield, the same bond sells at a premium: $1,081.76.
Limitations
- Settlement on a coupon date. Calcist assumes you buy right after a coupon is paid, so there's no accrued interest and the clean price equals the full (dirty) price. Between coupon dates, the seller is also owed accrued interest, and the quoted clean price excludes it.
- Years to maturity are rounded to a whole number of coupon periods.
- YTM assumes you hold to maturity, every payment is made, and coupons are reinvested at the YTM. It ignores call features, taxes and default risk.
- Yields are quoted the usual US way: the rate per period × periods per year. The effective annual yield is also shown.
This is a planning estimate, not financial, tax or investment advice.
Sources
How we checked this
Before every update, this calculator is run in a real browser with these known answers, and it must match all of them:
- $1,000 face, 5% coupon paid twice a year, 10 years, 6% YTM: $925.61 ✓
- Same bond: current yield 5.402% ✓
- At a 4% YTM it sells at a premium: $1,081.76 ✓
- Price $925.61 gives yield to maturity 6% ✓
- Zero-coupon, 10 years at 5%: $610.27 ✓
- 4% annual coupon, 5 years, price $950: YTM 5.16% ✓
Last checked October 26, 2026. Spotted something wrong? The math is done in your browser with the formula shown on this page, so you can check any result by hand.
Questions people ask
How do I calculate a bond's price?
Discount each coupon and the face value back to today at the yield per period, and add them up. A 5% coupon, 10-year $1,000 bond yielding 6% (semiannual) is worth $925.61.
Why do bond prices fall when yields rise?
The bond's coupons are fixed. When new bonds pay more, the old bond's price must fall until its yield matches the market.
What is the difference between current yield and yield to maturity?
Current yield only compares the yearly coupon with the price. YTM also counts the gain or loss from buying below or above face value and holding to maturity.
What is a premium or discount bond?
A bond priced above its face value trades at a premium (its coupon is above the market yield); below face value, at a discount.
What is duration?
Macaulay duration is the weighted average time until you receive the bond's cash flows, in years. Modified duration estimates the percent price change for a 1-point change in yield.