T-Bill Calculator
For informational purposes only. Rates change at every auction. Verify at TreasuryDirect.gov before investing.

Treasury Bill Yield Calculator

Enter a face value and discount rate to see yield and profit across every standard T-bill term — 4-week through 52-week.

Inputs

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All six standard terms at the rate above:

Term Days Purchase Price Discount Yield Inv. Yield (BEY) Profit

About These Calculations

The calculator uses the standard U.S. Treasury discount-yield formulas published by the U.S. Treasury and used in all official auction result publications:

  • Discount yield (auction-quoted rate): (FV − P) ÷ FV × (360 ÷ t)
  • Investment yield / BEY (apples-to-apples with CDs and bonds): (FV − P) ÷ P × (365 ÷ t)
  • Price from rate: P = FV × (1 − d × t/360)

Current auction rates are not stored in this tool. Find the latest rates at TreasuryDirect.gov → Auction Query.

Related: T-Bill Calculator (full)  |  T-Bill vs CD  |  I Bond Calculator  |  How T-Bills Work

Frequently Asked Questions

Why does a longer-term T-bill produce more dollar profit at the same discount rate?

A higher discount rate applies to more days, so the total discount from face value is larger for a longer maturity. A 52-week T-bill at 4% discount yields about $400 in profit on a $10,000 face-value bill, while a 4-week T-bill at the same 4% discount rate yields about $31.

Which T-bill term is auctioned weekly?

The 4-week, 8-week, 13-week, and 26-week T-bills are auctioned weekly. The 17-week bill is auctioned weekly as well. The 52-week bill is auctioned every four weeks.

What does BEY mean?

BEY stands for bond-equivalent yield. It converts the discount-basis yield to a 365-day-year return based on the price you actually pay, making it directly comparable to APY on CDs or the coupon yield on bonds.

Are rates different across T-bill terms?

Yes. Each term is auctioned separately and the market bids different discount rates for each maturity. Longer-term bills typically (but not always) carry slightly higher yields. This calculator applies one discount rate across all terms for comparison purposes.

Where can I find current T-bill auction rates?

TreasuryDirect.gov publishes all recent auction results. Check the "Recent Auction Results" page for the latest rates for each term.