Bond dirty price calculator: the clean price plus the cash you really pay
A bond quote leaves out the interest earned so far. You still pay it. Enter your bond and see the real bill.
How it works: the clean price is the quote on the screen. It leaves out the interest the bond has earned since its last coupon. That interest is called accrued interest. You pay it to the seller on top of the clean price. Clean price plus accrued interest is the dirty price. The dirty price is the cash that leaves your account. Accrued interest is the coupon times the days that have passed, divided by the days in the period. This page rounds it to the cent for each bond, then multiplies by the number of bonds.
The price on the screen is not the bill
A bond at 98.5 looks like a bargain under par. The cash you pay is higher. The extra is the seller's share of the next coupon. You get it back when the coupon pays, because the full coupon goes to whoever holds the bond that day. Only the days you held are yours. Compare this with bond yield, which looks at the price you paid, not the quote.
Where the mix-up starts
Most bond quotes are clean. Your statement shows the cash. If you only look at the quote, the trade seems cheaper than it was. The same split is behind many surprises in stocks versus bonds and bond ETFs versus single bonds. A trade also has a settlement day, and accrued interest runs to that day. Use the days to that day.
Follow along