Bond yield calculator

The yields follow the spreadsheet YIELD convention: coupon dates counted back from the redemption date, the chosen day-count basis for the accrued fraction, cash flows discounted from settlement, and the documented closed form when one coupon period or less remains. YTM and YTC come from bracketing and bisecting the remaining cash flows to machine precision, so you can check every number against your spreadsheet. A clean price of 95.04 means 95.04 % of face; the dirty price adds the accrued interest the seller keeps.

What this does not do: it holds the coupon schedule and redemption fixed, so there are no default or reinvestment assumptions, no tax, no inflation break-even, and no live market prices. Duration is the Macaulay measure to maturity with its modified derivative; it says nothing about convexity hedging. For municipal, inflation-linked, or amortizing structures the plain fixed-coupon model here is the wrong shape.