Bond Calculator

It takes any four of the five core bond inputs — price, yield, coupon, time to maturity, and face value — and solves for whichever one you left blank. Behind the scenes it discounts every future cash flow back to today and reports the things you actually care about: what a fair price looks like at a given yield, what yield you're earning at a given price, how much you'll collect in coupons, and how the price will move if rates shift. You don't need a finance textbook open to use it.

Because the price is the only thing that can adjust. The coupon is locked in at issuance. When the rest of the bond market starts demanding a higher yield, the only way to make your old, lower-coupon bond competitive is to drop the price. That extra discount becomes part of the new buyer's return. Same coupons, same maturity, different price — same total yield.

The coupon rate is what the issuer prints on the bond — a fixed percentage of face value paid each year. The current yield is the coupon divided by today's price, so it changes whenever the price moves. Yield to maturity (YTM) is the most complete number: it folds in the coupons, the price you paid, and any capital gain or loss you'll book when the bond matures at par. For comparing two bonds, YTM is the apples-to-apples figure.

Bonds quote the clean price (what the bond is worth ignoring any partially-earned coupon), but you actually pay the dirty price (clean + accrued interest). The seller has been holding the bond since the last coupon date, so they've earned a slice of the next coupon. You reimburse them now and collect the full coupon on the next payment date. By the time the cycle completes, it all evens out.

Not really. A high-coupon bond usually trades at a premium, so you pay extra upfront for that bigger paycheck. Over the life of the bond, that premium amortizes away and you end up roughly where you would have been with a par bond at the same yield. The income arrives sooner, but the total return depends on the YTM, not the coupon. The coupon decides cash-flow timing; YTM decides return.

It's a quick read on how much your bond's price will move when yields change. A modified duration of 7 means the bond loses roughly 7% if yields rise 1%, and gains roughly 7% if yields fall 1%. Short-term bonds have low duration and barely flinch when rates move. Long-term bonds — especially zero-coupon ones — have high duration and can swing 20%+ on a 1% rate change. Use it to size your interest-rate exposure.

Yes. Flip the zero-coupon toggle in Advanced Settings on the Bond Calculator tab. The math simplifies — there's only one cash flow, the face value at maturity — and the price is just the face value discounted back at the yield. Zero-coupon bonds also have the highest possible duration for any given maturity, so the sensitivity chart will show much larger price swings than a coupon bond at the same maturity.

Existing bond prices rise. The coupons on bonds already in circulation suddenly look more attractive than what new bonds are being issued at, so buyers bid the old bonds up until their yield matches the new lower rate. Long-duration bonds benefit the most — a 1% drop in yields can push a 20-year bond up 15% or more in price. The flip side: when the Fed hikes, the same math runs in reverse and long bonds drop hard.

Interest from corporate and most government bonds is taxed as ordinary income at the federal level. U.S. Treasury interest is federal-taxable but exempt from state and local tax. Municipal bond interest is generally exempt from federal tax — and sometimes from state tax if you buy in-state. If you sell a bond before maturity for more than you paid, the gain is a capital gain. Selling at a loss can offset other capital gains. Tax laws shift, so confirm specifics with a CPA before filing.

Individual bonds give you a known maturity date and a defined payout — useful for matching a future liability like college tuition or a home purchase. Bond funds give you instant diversification and professional management, but their share price floats with the market and they never truly mature. If you want a precise schedule of cash flows, individual bonds are clearer. If you want broad exposure to fixed income with low minimums, a fund is simpler. This calculator works for individual bonds; for funds, look at the fund's average YTM and average duration.