Bond Yield Calculator

What the bond yield calculator shows

This bond yield calculator works out the yield to maturity, the current yield and the after-tax yield of a fixed-rate bond from five things you know: its face value, the price you pay, the annual coupon rate, the maturity date and how often it pays. It then shows how many bonds your money buys, how much coupon income they pay year by year, and what you receive in total when the bonds are repaid.

It answers the questions investors ask before buying a Treasury note, a corporate bond or a zero-coupon bond: what will this bond return per year at this price, why is its yield different from its coupon, how much is lost to tax, and how far could the price move if rates rise before maturity?

The calculator runs entirely in your browser. Nothing you enter is sent anywhere.

In this guide:

• How to fill in each field and read the results, the chart and the payment schedule
• The exact method behind each yield and the rate sensitivity, and what it simplifies
• Coupon rate vs current yield vs YTM, and why bond prices fall when yields rise
• Duration, effective vs quoted yields, taxes, zero-coupon bonds and Treasury bills
• A yield lookup table, three worked examples in US dollars and common mistakes

If bonds are new to you, the basics article on what bonds are explains face value, coupons and maturity from the start.

How to use the bond yield calculator

The calculator opens in US dollars with a bond with a face value of 1,000 bought at 950, a 10% coupon paid quarterly, a maturity date five years from today and both tax fields at 0%. The UAH / USD / EUR switch sits in the header of the Your numbers panel, or under More options on phones and tablets; it changes only the symbol, with no conversion, and sets both tax fields back to 0%. The main inputs come first:

1. Purchase price. The quoted price of one bond, in currency, not as a percentage, and without accrued interest. A price quoted as 92 for a $1,000 bond is $920.
2. Annual coupon rate. The yearly interest rate printed on the bond, as a percentage of face value.
3. Maturity date. The day the bond is repaid, from tomorrow to 100 years ahead. Past days are greyed out in the calendar, a date outside the range moves to the nearest allowed day, and an incomplete date is ignored.
4. Your investment amount. How much money you plan to spend. The calculator buys as many whole bonds as it covers.

More options holds the rest, with the note that year 1 is the next 12 months:

5. Face value (par). The amount the issuer repays at maturity for one bond, such as $1,000. Coupons are calculated on this amount.
6. Coupon frequency. Annual, Semi-annual or Quarterly, chosen from a list that disappears when the coupon rate is 0.
7. Tax rate on coupon income. Your tax rate on each coupon payment.
8. Tax rate on redemption gain. Your tax rate on the gain when the bond is repaid above your purchase price.

On phones, Purchase price and Your investment amount have − and + buttons instead of sliders.

With both tax fields at 0%, the after-tax yield starts equal to the gross yield to maturity. For a US Treasury in a taxable account, enter your federal rate; for an account where the income is not taxed as it is paid, leave both tax fields at 0.

Reading the results

The headline is the After-tax yield, the annual return after both taxes if you hold to maturity. Six figures follow. Gross yield to maturity is the same calculation before tax. Current yield is the annual coupon before tax divided by your price. Rate sensitivity (per +1%) estimates the price change if the bond's yield rises by one percentage point. Total invested shows what your investment amount buys, with the number of bonds beside it. Total coupon income is all after-tax coupons until maturity, and Total return adds the after-tax gain or the loss at redemption.

The Chart and Payment schedule tabs count the bond's years from today. A semi-annual bond maturing in October 2036, entered in October 2026, has 20 coupons in ten rows, and the last row also carries the repayment. A zero-coupon bond has a row for each year up to the one that contains the maturity date.

Pin to compare keeps the current bond as a reference: the headline shows the change in after-tax yield, such as +0.56 pp vs pinned in Example 2, the chart adds a dashed line along the pinned bond's bars (a ringed dot if it matures within 12 months), and a caption sums it up. Switching the currency, Reset or a reload clears it. PDF exports the inputs, the eight results and the schedule, without the pin. Share shares a link without your numbers, and Reset restores the defaults. On phones and tablets, the results sit in a bar at the bottom of the screen that stays visible while you pick a date; Details opens the rest.

How the calculator works out yield to maturity

The calculator treats the bond as a simple series of equal coupon payments followed by the face value at maturity, then finds the discount rate that makes that series worth exactly what you pay.

Time to maturity and coupon periods

years = days from today to the maturity date ÷ 365.25
k = coupon payments per year (1, 2 or 4)
C = annual coupon rate × face value ÷ k
coupon dates = maturity date, then every 12 ÷ k months back, while after today
first coupon = C × days to the next coupon ÷ days in its period

A maturity date exactly five years away gives 20 quarterly or 10 semi-annual coupons in full, because today is then a coupon date. A semi-annual bond maturing on 16 February 2031, entered on 16 October 2026, has 9 coupons: the next, 123 days away in a 184-day period, counts 123 ÷ 184 = 67% of C. You pay the rest to the seller as accrued interest on top of the quoted price. A zero-coupon bond is one payment at maturity, timed in actual years.

Solving for yield to maturity

Price = CF₁ ÷ (1 + r)^(t₁ × k) + CF₂ ÷ (1 + r)^(t₂ × k) + … + (C + F) ÷ (1 + r)^(tₙ × k)
Gross YTM = (1 + r)^k − 1

• F is the face value, C the coupon per period and CF₁ the first coupon above
• t is each payment's time in years (days ÷ 365.25), n the number of coupons
• r is the unknown yield per coupon period, k the periods per year

The equation cannot be solved directly for r, so the calculator searches for it by halving a range of almost −100% to 1,000% per period 200 times. The result is converted to an effective annual yield by compounding the period rate k times. For the default bond, the solved quarterly rate turns into a Gross YTM of 11.81%.

Single payment: zero-coupon bonds and the last coupon period

Payment = F + first coupon (0 for a zero-coupon bond)
Gross YTM = (payment ÷ price)^(1 ÷ years) − 1
MD of a zero-coupon bond = years ÷ (1 + Gross YTM)

With one payment, the yield is solved directly over the actual time, so a zero's hidden frequency plays no part. A coupon bond in its last period keeps only the part of the coupon earned from today: a 4% bond at par with 28 days left in a 92-day quarterly period earns $3.04 of its $10.00 coupon and shows 4.04%. The share follows the real period length, so Annual (28 of 365 days) earns $3.07 and shows 4.08%.

After-tax yield, current yield and totals

After-tax coupon = C × (1 − coupon tax rate)
Gain = F − price; tax on gain = gain × redemption tax rate, only if the gain is positive
After-tax YTM: same equation with the after-tax coupon and F − tax on gain
Current yield = annual coupon before tax ÷ price
Total return = sum of after-tax coupons + gain − tax on gain, for each bond bought

Current yield is the textbook figure, the annual coupon before tax divided by the price. For the defaults, 10% of 1,000 is 100, and 100 divided by 950 is 10.53%. The coupon tax lowers only the after-tax yield and the money figures.

Rate sensitivity

Macaulay duration = Σ (t in years × present value of each payment) ÷ price
MD = Macaulay duration ÷ (1 + r)
Rate sensitivity = −MD %

The duration uses the gross cash flows and the gross yield. For the default bond, MD is 3.85, so the figure shows −3.85%.

Assumptions behind the numbers

• Fixed coupon, paid on time, and the face value repaid in full at maturity. No default, call or early redemption.
• Quoted price, partial first coupon. The price excludes accrued interest, so the next coupon counts only from today.
• Coupon dates from the maturity date. Coupons fall every 12 ÷ k months back from maturity, with no business-day shifts.
• Hold to maturity. The yields assume you keep the bond until it is repaid.
• No reinvestment in the money figures. Coupons are added up as cash; only the YTM itself implies reinvestment at the same rate.
• Simple tax model. Each coupon is taxed when paid, a gain is taxed once at maturity, and a loss is neither taxed nor offset against coupon tax.
• Not modelled: commissions, markups, inflation, exchange rates, state taxes as a separate item, and yield to call.

Coupon rate, current yield and yield to maturity

Three percentages describe a bond, and they are equal only when you buy at face value.

• Coupon rate is fixed at issue: FINRA defines it as the annual interest rate established when the bond is issued that does not change. It tells you the coupon in dollars, not your return.
• Current yield is the annual coupon divided by the price you pay. It ignores the gain or loss at maturity.
• Yield to maturity adds that gain or loss, spread over the years you hold the bond.

The table uses a five-year bond with a $1,000 face value and a 5% semi-annual coupon, with both tax fields at 0:

Every bond pays the same $250.00 of coupons. Below par, the gain at maturity lifts YTM above the current yield; above par, the loss pulls it below. At par, YTM is 5.06% rather than 5.00% only because the calculator compounds the two semi-annual payments, explained below.

The practical rule: for a bond bought at a discount, current yield understates the return; for a bond bought at a premium, it overstates it. For a bond you plan to hold to maturity, YTM is the figure to compare.

Why bond prices fall when yields rise

A bond's coupons are fixed, so the only way its yield can follow the market is through its price. The SEC's investor bulletin on interest rate risk puts it plainly: market interest rates and bond prices move in opposite directions. TreasuryDirect's pricing page shows the same rule for Treasury notes and bonds: when the yield is higher than the interest rate, the price was lower than par value, and when it is lower, the price is above par.

The table takes a 10-year bond with a $1,000 face value and a 4% semi-annual coupon. This guide computed the price at each yield; entering that price in the calculator returns exactly that Gross YTM.

This matters only if you sell before maturity. As the SEC bulletin notes, if you hold a bond to maturity, you will be paid the stated interest rate, as well as the face value, whatever the price did in between. The trade-off between a safer return and a higher one is covered in risk and return.

Rate sensitivity and duration explained

The Rate sensitivity figure answers the question "how much could I lose if rates rise?" FINRA describes duration as a measure of how much a bond investment is likely to change in value, with a rule of thumb: for every 1 percentage-point change in interest rates, a bond will rise or fall in the opposite direction by roughly its duration.

Modified duration grows with maturity and shrinks as the coupon rises. The table shows the calculator's Rate sensitivity for semi-annual bonds priced to a 4.00% Gross YTM (prices computed by this guide):

A zero-coupon bond's duration is its years to maturity divided by one plus the yield, because all its value is paid at the end. A 6% coupon returns cash sooner, so a 30-year bond with a 6% coupon is less sensitive than a 30-year zero. The zero is measured against the effective yield and the coupon bonds against twice the six-month yield, so at two years it reads just below the 2% bond (−1.96% on the coupon basis).

The estimate is a straight line

Modified duration is a linear approximation. Real prices curve, a property called convexity: they rise more than the estimate when yields fall and fall less when yields rise. The table uses the 10-year 4% bond bought at par, with a Rate sensitivity of −8.18%, and moves the Gross YTM shown by the calculator. The exact prices were computed by this guide.

For a one-point move the estimate is close; for larger moves it overstates the loss. Part of the gap is basis: for a coupon bond, the duration is measured against the period yield times the periods per year, not the effective yield displayed, so the figure runs slightly large.

Effective annual yield vs quoted bond yields

The calculator expresses every yield as an effective annual rate, so a bond that pays four times a year and one that pays once can be compared like for like. Most published US bond yields use a different convention. The US Treasury's interest rate FAQ says its constant-maturity yields represent "bond equivalent yields" for securities that pay semiannual interest, expressed on a simple annualized basis, and that they are not effective annualized yields.

Bond-equivalent yield = 2 × ((1 + effective YTM)^(1/2) − 1)
Effective YTM = (1 + bond-equivalent yield ÷ 2)^2 − 1

For semi-annual bonds bought at par, the bond-equivalent yield equals the coupon rate. The calculator's figure is slightly higher:

Coupon frequency has the same effect. A 10-year bond bought at par with a 5% coupon shows a Gross YTM of 5.00% with annual coupons, 5.06% with semi-annual coupons and 5.09% with quarterly coupons, because coupons that arrive sooner can be reinvested sooner, as compound interest explains.

Taxes and after-tax bond yield

Tax often changes which bond is the better buy, so the calculator has two tax fields. Some US rules worth knowing before you fill them in:

• Treasury interest is subject to federal income tax but is exempt from all state and local income taxes, according to the IRS (page reviewed October 7, 2026). TreasuryDirect states the same for Treasury notes.
• Interest on many state and local government bonds is reportable but not taxable at the federal level, per the same IRS page.
• Market discount. If you buy a bond below par on the secondary market and do not choose to include the discount in income each year, IRS Publication 550 says you must treat any gain when you dispose of the bond as ordinary interest income, up to the amount of the accrued market discount. For a discount Treasury held to maturity, that usually means the redemption field takes your ordinary income rate, not a capital gains rate.
• Original issue discount. Publication 550 also says OID is generally included in income as it accrues over the term, whether or not you receive any payments. The calculator taxes the gain only at maturity, which overstates the after-tax yield of a taxable zero-coupon bond.
• Premium bonds. If you pay above par, Publication 550 lets you choose to amortize the premium to reduce the taxable interest each year. The calculator does not model this: it taxes the full coupon and gives no tax relief for the loss at maturity.

The table takes a 10-year Treasury-style bond with a 4% semi-annual coupon bought at $920, with the same rate in both tax fields. The rates are illustrative.

For a corporate bond, state income tax applies too; adding your state rate to your federal rate in both fields gives a rough combined figure. After-tax yield is also the fair way to compare a bond with a deposit, which the deposit vs investment calculator does for savings and funds.

Zero-coupon bonds and Treasury bills

A zero-coupon bond pays no coupons. You buy it below face value and the whole return is the gain at maturity. Set Annual coupon rate to 0: Coupon frequency and the Coupon payments column disappear, and Current yield shows 0.00%.

A five-year zero with a $1,000 face value bought at $800 shows a Gross YTM of 4.56%, (1,000 ÷ 800)^(1 ÷ 5) − 1, and a Rate sensitivity of −4.78%, about 5 ÷ 1.0456.

Treasury bills work the same way. TreasuryDirect explains that bills are sold at a discount or at par, for terms from four to 52 weeks, and that the interest is the difference between what you paid and the face value at maturity. The calculator handles every term:

The last column was computed by this guide, not the calculator, as (face − price) ÷ price × 365 ÷ days. It approximates the investment rate TreasuryDirect publishes, which its glossary defines as an annualized simple interest rate based on a 365-day year, without compounding. The calculator compounds the return over a full year, so it is higher for short bills, and the two meet at 52 weeks.

Bond yields at a glance

This grid shows the calculator's Gross YTM for a bond with a 5% semi-annual coupon, by purchase price as a percentage of face value and by years to maturity. Both tax fields are 0.

A given discount or premium matters most when maturity is near, because the gain or loss is spread over fewer years: at 85, a two-year bond yields 14.31% and a 20-year bond 6.43%. And a high price can wipe out the coupon entirely: a two-year 5% bond bought at 110 yields 0.00%, because the $100 loss at maturity equals the two years of coupons. Current yield ignores both effects; at 85 it is 5.88% whatever the maturity.

Worked examples

Each example uses USD and shows what the calculator returns. Maturity dates are counted from October 16, 2026; if you enter them later, use a date the same number of years ahead. The prices and tax rates are illustrative.

Common mistakes when calculating bond yield

• Entering the price as a percentage. Bond prices are often quoted per 100 of face value. Convert to currency per bond: 98.5 on a $1,000 bond is $985.
• Comparing the calculator's YTM with a quote on a different basis. Quoted US yields for semi-annual bonds are bond-equivalent yields, and Treasury bill investment rates are simple rates; both are slightly below the effective yield shown here. Convert before you compare.
• Judging a bond by its coupon. A high coupon bought at a premium can yield less than a lower coupon bought at par, as Example 2 shows.
• Relying on current yield for discount or premium bonds. It ignores the gain or loss at maturity. Use YTM for anything you plan to hold.
• Leaving the tax fields at 0 for a taxable bond. Both open at 0%; enter your own rates.
• Forgetting that YTM needs the bond to be held. If you sell early, your return depends on the price at that time; the Rate sensitivity figure shows how far it could move.

Limitations and next steps

This calculator covers a fixed-rate bond held to maturity. It does not model the issuer's exact day-count rule, calls, defaults, floating or inflation-linked coupons, reinvestment income, commissions, or the yearly taxation of discount, and it cannot tell you whether an issuer will pay, what rates will do, or whether a bond fits your plan.

Use it to compare bonds on equal terms, then look at the rest of your finances:

• The inflation impact calculator shows what a fixed coupon and the face value will be worth in today's money.
• The compound interest calculator shows what coupons could grow to if you reinvest them.
• The deposit vs investment calculator compares a safe deposit with a riskier investment after tax and fees.
• The passive income calculator shows how much capital a target monthly income from coupons would take.

For background, read what bonds are, how they compare with other types of investment assets, and why a fixed coupon loses value in real terms in inflation and why money loses value. For decisions about your own portfolio or tax situation, consider a qualified, independent adviser or tax professional.