Bond Equivalent Yield Calculator

Convert a short-term discount instrument into an annualized bond-equivalent yield. This page also keeps the formula, examples, FAQs, and references close by so you can check the result with confidence.

What This Bond Equivalent Yield Calculator Helps You Do

Bond equivalent yield annualizes the discount between face value and purchase price using the time to maturity. Review the formula and examples below if you want to see how the result is derived.

This page is meant to give you a fast answer, but it also helps you double-check the math before you make a decision. Start with the inputs that you already know, run the calculation, and then compare the output with the formula, examples, and FAQs below so you can see whether the answer fits the situation you are modeling.

If the result looks off, the usual causes are a unit mismatch, a missing decimal, the wrong scenario, or a value that needs to be entered as a rate instead of a total. The notes on this page are designed to make those checks easy without forcing you to leave the calculator and search for context elsewhere.

  • Use the calculator first for a quick estimate.
  • Use the formula to understand how the result is built.
  • Use the examples to compare common use cases.
  • Use the references when the answer depends on a standard or assumption.

Common Checks

A quick result is useful, but the best result is one that still makes sense when you look at it a second time. If you are comparing scenarios, try changing one input at a time so you can see which variable has the biggest impact on the final answer. That makes it much easier to spot whether the calculation matches your expectations.

It also helps to keep the context of the problem in mind. A calculator can tell you the math, but you still need to decide whether the input represents a total, a rate, an average, or a category-specific assumption. When in doubt, start with a simple example from the page and scale up from there.

  • Check that every unit matches the rest of the problem.
  • Keep rates, totals, and averages separate.
  • Adjust one variable at a time when testing scenarios.
  • Use the smallest realistic input first, then scale upward.

Scenario Planning

This calculator is especially useful when you want a quick answer before you commit time, money, or effort. Try one baseline input set, then change a single number and compare the result so you can see how sensitive the answer is to that variable.

That makes the page useful for more than just arithmetic. It becomes a small decision aid that helps you compare options, test assumptions, and explain the final number with confidence when you need to share it with someone else.

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Result

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Quick Answer: Bond equivalent yield annualizes the discount between face value and purchase price using the time to maturity. Review the formula and examples below if you want to see how the result is derived.

How to Calculate Bond Equivalent Yield Calculator

  1. Enter the face value: Use the amount repaid at maturity.
  2. Enter the purchase price: Use the amount you pay today.
  3. Set days to maturity: Use the remaining days on the bill.

Bond Equivalent Yield Calculator Formula

BEY = ((Face value - Purchase price) / Purchase price) x (365 / Days to maturity)
Variable Meaning Unit
Face value Redemption value at maturity $
Purchase price Amount paid today $
Days to maturity Remaining days until maturity days

Worked Examples

USA - Treasury bill
  • Face value: $1,000
  • Purchase price: $975
  • Days to maturity: 180

Result: 5.07%

A modest discount on a half-year bill annualizes to about five percent.

UK - Short bill
  • Face value: £10,000
  • Purchase price: £9,875
  • Days to maturity: 90

Result: 5.06%

A shorter maturity increases the annualized yield from the same discount.

EU - Deep discount
  • Face value: €1,000
  • Purchase price: €960
  • Days to maturity: 120

Result: 12.71%

A bigger discount creates a much higher bond-equivalent yield.

BEY reference

Useful Treasury-bill checkpoints.

Range Meaning Action
Lower BEY Smaller annualized discount return Compare with other short-term instruments.
Typical BEY Common money-market style return Use it to compare against bond yields.
Higher BEY Large annualized discount return Check whether the discount reflects greater risk or shorter maturity.
Useful Treasury-bill checkpoints.
Metric Meaning Notes
Face value Redemption amount Paid at maturity
Purchase price Amount paid today Lower price raises BEY
Days to maturity Remaining term Shorter terms annualize faster

Frequently Asked Questions

It is an annualized return measure used to compare discount instruments with bond yields.

Bond equivalent yield typically annualizes the return on a 365-day basis.

It is a simple annualized return measure and does not model reinvestment compounding.
Planning note: This calculator uses a standard annualization approach for discount instruments.

References

Last reviewed: March 30, 2026