How this calculation works
A bond’s quoted clean price normally excludes the interest accrued within the current coupon period. The invoice amount adds the applicable accrued interest. Comparing a quote directly with cash settlement can therefore mix two different price definitions. This page reconciles them for one entered equal-coupon period using an explicit actual-days fraction. It does not derive yield or replace a bond’s documented market day-count convention.
Accrued = face × coupon/frequency × actual elapsed/actual coupon-period days; dirty value = clean quoted value + accruedA worked example
Face one thousand, annual coupon ten percent and two payments per year give a full coupon of fifty. Between 1 January and 1 July 2026 there are 181 actual days; settlement on 1 April has ninety elapsed days. Accrued interest is fifty times ninety divided by 181, about 24.8619. A clean quote of ninety-eight gives clean value 980 and dirty value about 1004.8619 before fees.
Good to know
Ex-coupon periods, irregular short or long coupons, holiday rules, withholding and settlement fees are excluded. The dates are supplied rather than generated from a security identifier. No live quote, yield estimate or investment advice is provided. Verify the actual bond’s convention before interpreting a difference from a broker’s invoice as an error.
Reference: FINRA — accrued interest calculator (opens in a new tab) ↗
What this calculation answers
A bond’s quoted clean price normally excludes the interest accrued within the current coupon period. The invoice amount adds the applicable accrued interest. Comparing a quote directly with cash settlement can therefore mix two different price definitions.
This page reconciles them for one entered equal-coupon period using an explicit actual-days fraction. It does not derive yield or replace a bond’s documented market day-count convention.
The Bond price and yield to maturity calculator derives bond present value from a yield scenario. Clean-to-dirty reconciliation additionally needs the correct coupon-period accrual convention.
Use the right input conventions
Face amount is the amount held, while clean price is quoted per one hundred face. Annual coupon rate and payment frequency determine one full equal coupon amount.
Enter previous and next coupon dates with settlement on or after the previous date and strictly before the next. Settlement on a coupon date starts a new period instead of accumulating a full old coupon again.
Interpret the result
The elapsed fraction is actual days since the previous coupon divided by actual days in the entered coupon period. It is not automatically Actual/365, 30/360 or a complete market-specific Actual/Actual standard with stub rules.
Dirty price per one hundred and dirty currency value are reported separately. The held face amount scales cash accrued but does not change the per-one-hundred quote adjustment.
Work through the example
Face one thousand, annual coupon ten percent and two payments per year give a full coupon of fifty. Between 1 January and 1 July 2026 there are 181 actual days; settlement on 1 April has ninety elapsed days.
Accrued interest is fifty times ninety divided by 181, about 24.8619. A clean quote of ninety-eight gives clean value 980 and dirty value about 1004.8619 before fees.
Where the model stops
Ex-coupon periods, irregular short or long coupons, holiday rules, withholding and settlement fees are excluded. The dates are supplied rather than generated from a security identifier.
No live quote, yield estimate or investment advice is provided. Verify the actual bond’s convention before interpreting a difference from a broker’s invoice as an error.
A few questions, answered
Why is accrued interest added to clean value only once?
The clean quote excludes it; adding it again after computing dirty value would double-count the same coupon accrual.
What changes in the comparison?
Set settlement to the previous coupon boundary and inspect zero accrual.