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Bonds & RatesCalculator

Bond yield calculator

Work out a bond's current yield and approximate yield to maturity from its price, coupon and years left. Formula and worked example included.

Bond yield calculator

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Most bonds are quoted per $100 or $1,000 of face value.

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Result

Yield to maturity (approx.)
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Current yield
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Yearly coupon income
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Quick answer

Current yield is the yearly coupon divided by the price you pay. Yield to maturity is the yearly return if you hold the bond to the end, counting coupons and the gain or loss back to face value. Buying below face value pushes both above the coupon rate.

A vintage desktop calculator with a red display
“Texas Instruments Longines Symphonette Calculator 1st version” by Mister rf — CC BY-SA 4.0 (edited: cropped, recolored)

What do the two yields mean?#

Investor.gov defines current yield as the ratio of the interest payable on a bond to its actual market price, stated as a percentage[1]. The SEC's bulletin on corporate bonds describes yield to maturity as the annual return if the bond is held to maturity, taking into account when you bought it and what you paid[2].

How is the result calculated?#

  1. Yearly coupon = face value × coupon rate.
  2. Current yield = yearly coupon ÷ price.
  3. Yield to maturity = the rate that makes the present value of all remaining coupons plus the face value equal to the price. The calculator finds it by trial (bisection), assuming every payment is made on time.

Worked example

$1,000 face, 5% coupon, price $950, 10 years, semiannual coupons

The yearly coupon is $50. Current yield is $50 ÷ $950 = 5.26%. Yield to maturity is about 5.66%, higher than the current yield because you also gain $50 when the bond repays $1,000 at maturity.

PriceCurrent yieldYield to maturity
$950 (discount)5.26%5.66%
$1,000 (par)5.00%5.00%
$1,050 (premium)4.76%4.38%

Figures computed in code from the stated inputs; rounded to the nearest cent or tenth.

What does this calculator assume?#

  • Every coupon and the face value are paid in full and on time — there is no default. FINRA notes that yield to maturity assumes coupon and principal payments are made on time[4]. Credit risk is covered in credit ratings explained.
  • Coupons are reinvested. You do not have to reinvest them, but FINRA notes that yield-to-maturity computations generally make that assumption[4].
  • No call features, taxes or trading costs.
  • The price you enter is treated as the full amount you pay. The calculator ignores accrued interest — interest earned on a security but not yet paid[5].

What mistakes do beginners make?#

  1. Comparing a coupon rate with a yield

    The coupon rate is fixed at issue; yields depend on today's price. Compare yields with yields.

  2. Forgetting credit risk

    Non-investment-grade (high-yield) bonds generally offer higher interest rates to compensate investors for greater risk[2]. The calculator assumes every payment arrives.

What else do beginners ask?#

Why is yield to maturity different from the coupon rate?

The coupon rate is fixed when the bond is issued. Yield to maturity depends on the price you pay today, so it changes as market prices change[2].

Which yield should I compare between bonds?

The SEC calls yield to maturity a widely used measure to compare bonds[2]; it includes the gain or loss back to face value. Current yield only looks at this year's coupon income.

Sources

Numbers in brackets in the text point here. Grade A = primary source (regulator, statistics agency, law or official document).

  1. 1
    Current Yield (glossary)U.S. SEC — Investor.gov (n.d.) · Grade A
  2. 2
    What Are Corporate Bonds? – Investor BulletinU.S. SEC — Investor.gov (n.d.) · Grade A
  3. 3
    Bonds and Yields (Back to Basics)IMF — Finance & Development (2025) · Grade A
  4. 4
  5. 5
    Accrued Interest (glossary)U.S. SEC — Investor.gov (n.d.) · Grade A

How we checked this note

Every number, date and rule above links to its source. This note cites 5 sources, 5 of them primary (Grade A). Worked examples were calculated in code, and a second editor compared each figure with its source before publishing. Spotted an error? Tell us — corrections are listed on the note. Read our editorial policy.