THE NUMORIX GUIDE
How to use the Bond Calculator
Last reviewed September 14, 2026
What this calculator does
The engine calculates periodic coupon payment as face value x coupon rate / frequency, current yield as annual coupon divided by current price, and total coupons as periodic coupon times years to maturity times frequency.
Formula and method
The engine calculates periodic coupon payment as face value x coupon rate / frequency, current yield as annual coupon divided by current price, and total coupons as periodic coupon times years to maturity times frequency. It then uses Newton iteration on the bond pricing equation that discounts every coupon and the face value at periodic yield to approximate yield to maturity.
Variables and inputs
Enter face value, coupon rate, years to maturity, coupon frequency of annual, semiannual, quarterly, or monthly, and current market price. Face value, price, and coupon payment are dollars; coupon rate and yields are percentages.
Worked example
For a $1,000 face-value bond with a 5% coupon, 10 years to maturity, semiannual coupons, and a $950 market price, each coupon is 1,000 x 0.05 / 2 = $25. Annual coupon is $50, so current yield is 50 / 950 x 100 = 5.26%; total coupons are 25 x 20 = $500. Because price is below par, the YTM is above the 5% coupon rate.
How to interpret the result
Current yield uses only the coupon and current price. YTM also accounts for the price moving toward face value at maturity and reinvestment assumptions implicit in the discount rate. A lower price generally raises yield for a fixed coupon, all else equal.
Common mistakes to avoid
Enter current price per bond, not the original purchase total for a different number of bonds. Match coupon frequency to the contract. Do not compare current yield with YTM as if they were the same measure.
Assumptions and limitations
The route assumes regular coupons, a single maturity payment, and a Newton approximation. It omits accrued interest, call or put features, default risk, taxes, reinvestment risk, settlement dates, and day-count conventions. Invalid extreme prices or rates can affect numerical convergence.