T-Bill Discount Yield & Bond Equivalent Yield (BEY) Calculator

Convert T-Bill face value and maturity days into purchase price and annualized BEY.

Bond Equivalent Yield (365-Day BEY)
4.93 %
T-Bill Auction Purchase Price USD 9,878.67
Dollar Interest / Discount Earned USD 121.33
Quoted 360-Day Discount Rate 4.8 %
Inputs
Amounts are treated in the selected currency; no foreign-exchange conversion is applied.
currency
Treasury bill par value at maturity.
% / yr
Quoted 360-day bank discount rate (%).
days
Days until maturity (e.g., 28, 91, 182, or 364 days).
Results & Graph
Bond Equivalent Yield (365-Day BEY)
4.93 %
T-Bill Auction Purchase Price
USD 9,878.67
Dollar Interest / Discount Earned
USD 121.33
Quoted 360-Day Discount Rate
4.8 %

Bond Equivalent Yield (365-Day BEY)

Graph 1 • Face Value Sensitivity Recalculates the domain equation across 50% to 150% of the primary input while holding other parameters constant.
0 % 2.7 % 5.3 % 50%: 4.93 % 4.9 50% 75%: 4.93 % 4.9 75% 100%: 4.93 % 4.9 100% 125%: 4.93 % 4.9 125% 150%: 4.93 % 4.9 150%
Graph 2 • Primary & Supporting Metric Comparison Compares the primary output alongside supporting domain benchmarks.
Bond Equivalent Yield (365-Day BEY) 4.93 % T-Bill Auction Purchase Price USD 9,878.67 Dollar Interest / Discount Earned USD 121.33 Quoted 360-Day Discount Rate 4.8 %
Graph 3 • Exact Output Table & Units Displays each calculated output in its exact domain unit.
Bond Equivalent Yield (365-Day BEY)4.93 %T-Bill Auction Purchase PriceUSD 9,878.67Dollar Interest / Discount EarnedUSD 121.33Quoted 360-Day Discount Rate4.8 %
Summary: Purchase price is USD 9,878.67 (USD 121.33 discount return), equating to a 4.926% annualized Bond Equivalent Yield.
Summary: Purchase price is USD 9,878.67 (USD 121.33 discount return), equating to a 4.926% annualized Bond Equivalent Yield.

Formula & Mathematical Methodology: T-Bill Yield Financial Formula

Price = Face × [1 − (DiscountRate × Days / 360)]
BEY = [(Face − Price) / Price] × (365 / Days)
Price = Face × [1 − (DiscountRate × Days / 360)]; BEY = [(Face − Price) / Price] × (365 / Days)
  • faceValue: Face Value (currency)
  • discountRatePct: Discount Rate Pct (% / yr)
  • daysToMaturity: Days To Maturity (days)

Rounding: Internal compounding uses full floating-point precision; currency outputs round to 2 decimal places.

Worked Example: Financial Planning Example: T-Bill Yield

Convert T-Bill face value and maturity days into purchase price and annualized BEY.

  1. Select your preferred display currency and enter your current financial figures.
  2. Evaluate the governing financial equation: Price = Face × [1 − (DiscountRate × Days / 360)]; BEY = [(Face − Price) / Price] × (365 / Days).
  3. Review the primary result, supporting breakdown, and 3 interactive SVG charts.
Result: Evaluates T-Bill Yield using Price = Face × [1 − (DiscountRate × Days / 360)]; BEY = [(Face − Price) / Price] × (365 / Days).

Frequently Asked Questions

How does the T-Bill Discount Yield & Bond Equivalent Yield (BEY) Calculator compute its result?

It evaluates Price = Face × [1 − (DiscountRate × Days / 360)]; BEY = [(Face − Price) / Price] × (365 / Days) using your entered parameters and updates all three custom financial charts in real time.

Does changing the currency convert exchange rates?

No. Selecting USD, INR, GBP, EUR, or any of the 150+ currencies formats all monetary amounts in your chosen denomination.

Are my financial numbers kept private?

Yes. All calculations run 100% locally in your browser with zero external server requests.

Finance & Investing • Fixed Income & Bonds Guide

How to Use the T-Bill Discount Yield & Bond Equivalent Yield (BEY) Calculator: Practical Guide & Visual Analysis

Calculate zero-coupon Treasury Bill purchase price, dollar discount, 360-day bank discount yield, and 365-day Bond Equivalent Yield (BEY). Supports 150+ display currencies, textbook mathematical formulas, and three custom SVG financial visualizations. Whether you are researching t-bill discount yield & bond equivalent yield (bey) calculator, t-bill yield, treasury bill discount bond equivalent yield, fixed income & bonds calculator, this interactive tool helps you calculate zero-coupon Treasury Bill purchase price, dollar discount, 360-day bank discount yield, and 365-day Bond Equivalent Yield (BEY).

Interpreting the 3 Custom Visual Graphs & Key Outputs

As you adjust Display Currency, Face Value, Discount Rate Pct, Days To Maturity, the calculator immediately computes Primary financial result, Supporting cash-flow & yield metrics, 3-Panel custom financial SVG charts and updates all three domain-specific SVG charts in real time. Instead of relying on a single static figure, you can inspect the primary domain diagram, component breakdown, and multi-point trajectory curve to see how changing your inputs shifts the final result. Use the Compare (up to 3 scenarios) button to evaluate side-by-side variations before making a decision.

Real-World Benchmark & Planning Tips (Global & India Financial Planning Reference)

In our benchmark scenario (Financial Planning Example: T-Bill Yield), Evaluates T-Bill Yield using Price = Face × [1 − (DiscountRate × Days / 360)]; BEY = [(Face − Price) / Price] × (365 / Days). Keep in mind that rates, yields, and tax percentages are treated as constant over the modeled horizon unless varied in scenario comparison. For related calculations in Finance & Investing, explore Compound Interest Calculator, Loan & EMI Calculator, SIP Calculator (Systematic Investment Plan).