Credit Spread Calculator
Solve a bond’s nominal yield to maturity and compare it with a matched benchmark yield in percentage points and basis points.
Earlier editorial review
- Reviewed
- 2026-09-18
- Methodology
- 1.1
Sources
How the calculation works
Enter the bond price and face value in the same currency and unit, the annual coupon rate, years to maturity, coupon payments per year, and a benchmark yield.
The model rounds maturity to a whole coupon period and discounts each coupon plus face value at one periodic yield. The price is treated as a coupon date value with the first payment one period away.
Nominal annual yield equals periodic yield times payment frequency. Credit spread is that yield minus the manually entered benchmark. One percentage point equals 100 basis points.
Review the modeled period count and maturity alongside yield to maturity, current yield, spread, and basis points. Match benchmark currency, maturity, and quote convention before comparing the result.
Step by step
- Enter price, face value, annual coupon rate, maturity, coupon frequency, and benchmark yield.
- Review the calculated yields, spread units, and modeled coupon timing.
- Compare only with a benchmark that uses a matching currency, maturity, and nominal yield convention.
Worked example
Use bond price 950, face value 1,000, annual coupon rate 5%, maturity 10 years, benchmark yield 4%, and two payments per year. The model has 20 coupon periods and returns nominal annual YTM of about 5.6617% and current yield of 5.2632%.
The spread is about 1.6617 percentage points, or 166.17 basis points. The unit test checks the cash flow price, yield, current yield, spread conversion, and a par bond case.
When to use this calculator
Use this calculator to solve a regular coupon bond’s yield and compare it with a manually entered benchmark on a matched basis.
Use the result as a yield comparison under the stated cash flow assumptions. It is not a rating, default probability, total return forecast, or option adjusted spread.
Common input mistakes
Using a benchmark with a different maturity or currency makes the spread comparison less meaningful. Treasury yield and bond yield must also use the same nominal or effective quoting basis.
Current yield is not yield to maturity. A clean price and a price with accrued interest are different quote conventions, while this model assumes a coupon date price without accrued interest.
Formulas
coupon = face_value × coupon_rate / 100 / payments_per_year
periods = round(years_to_maturity × payments_per_year)
bond_price = sum(coupon / (1 + periodic_yield)^t) + face_value / (1 + periodic_yield)^periods
nominal_annual_YTM = periodic_yield × payments_per_year × 100
credit_spread = nominal_annual_YTM − benchmark_yield
spread_basis_points = credit_spread × 100
current_yield = coupon_rate × face_value / bond_price
The bond price is modeled on a coupon date, immediately after a coupon payment, with the first payment one full period later. Accrued interest and dates between coupon payments are not modeled. Maturity is rounded to the nearest whole coupon period. Inputs that round to fewer than one period are invalid.
Limitations and assumptions
The model assumes regular fixed coupons, repayment of face value, and no default. It does not include accrued interest, payment dates between coupons, calls, puts, sinking funds, recovery, taxes, fees, or embedded option valuation. The benchmark yield is an input, not a fetched market quote.
Key terms
- Current yield
- The bond’s annualized coupon cash amount divided by its market price. It does not include principal gain or loss.
- Yield to maturity
- The periodic discount rate that makes the modeled coupon and face value payments equal the entered price, reported as a nominal annual rate.
- Credit spread
- The difference between nominal annual bond yield and a manually entered benchmark yield using a comparable quoting basis.
Related calculations
Bond Yield to Maturity solves yield from regular coupon cash flows. Bond Convexity describes how bond price sensitivity changes as yield moves.
Compare the benchmark only when currency, maturity, and quoted yield convention match. A spread is not a pure default probability or an option adjusted spread.
FAQ
What does this credit spread calculator measure?
It subtracts the entered benchmark yield from the bond’s solved nominal annual yield to maturity. The result is shown in percentage points and basis points. It compares yields under the entered cash flow assumptions, not total returns.
How is yield to maturity calculated?
The calculator finds the periodic rate that discounts the remaining coupon payments and face value to the entered price. It multiplies that rate by payments per year to report a nominal annual yield. The benchmark should use the same maturity, currency, and quote convention.
How does current yield differ from yield to maturity?
Current yield is the annual coupon cash amount divided by bond price. It excludes principal gain or loss and the timing of payments. Yield to maturity accounts for the modeled coupons and repayment of face value, assuming the promised cash flows arrive as entered.
Why can modeled maturity differ from the years I enter?
The calculator rounds years times payments per year to the nearest whole period. It rejects inputs that round to fewer than one period. It reports both the modeled period count and resulting maturity in years.
Does the price include accrued interest?
The model places the valuation on a coupon date, immediately after a payment, and assumes the next coupon is one full period away. It does not calculate accrued interest or interpolate dates between coupons. A bond quote between coupon dates may use a different price convention.
Related tools
Bond Yield to Maturity calculates yield from coupon cash flows. Bond Convexity examines the curvature of price sensitivity as yield changes.