Bonds: US Treasury Yield Curve & Calculators
The latest US Treasury daily par yield curve, sourced and dated, plus bond price, yield-to-maturity, current yield and duration calculators. No live quotes, no recommendations.
US Treasury daily par yield curve End of day
Par yields for September 25, 2026, as published by the US Department of the Treasury. A "par yield" is the coupon rate a hypothetical Treasury security of that maturity would need to carry to be priced at exactly 100 (par) today.
| Maturity | Yield |
|---|---|
| 1 Month | 4.04% |
| 1.5 Month | 4.14% |
| 2 Month | 4.20% |
| 3 Month | 4.24% |
| 4 Month | 4.32% |
| 6 Month | 4.33% |
| 1 Year | 4.50% |
| 2 Year | 4.81% |
| 3 Year | 4.94% |
| 5 Year | 4.98% |
| 7 Year | 5.06% |
| 10 Year | 5.17% |
| 20 Year | 5.54% |
| 30 Year | 5.49% |
Source: US Department of the Treasury — Daily Treasury Par Yield Curve Rates, data for 09/25/2026. This is an official end-of-day snapshot, not a live feed — check the source page for the current date's rates.
Table above refreshed from /data/invest/treasury-yields.json, fetched daily from the Treasury's own published CSV (see scripts/fetch-invest-treasury.js).
Bond price, yield & duration calculators
Standard bond math: price from a yield, yield from a price, current yield, and interest-rate sensitivity (duration). The yield-to-maturity field below is pre-filled with the 10-year point from the yield curve above (5.17%) — change it for any bond you're looking at.
Price from yield
Clean price — no accrued interest. Notice how price falls below face value (a "discount") when the coupon is lower than the yield to maturity, and rises above it (a "premium") when the coupon is higher.
Yield from price
Duration (interest-rate sensitivity)
Modified duration is roughly the % change in a bond's price for a 1-percentage-point move in yield, in the opposite direction — e.g. a modified duration of 7.5 means a 1-point rise in yield cuts price by about 7.5%.
What the yield curve shape means
The "yield curve" is just the yield-to-maturity of otherwise-similar bonds plotted against how long until they mature. For US Treasuries, the par yield curve above shows what a newly-issued Treasury security of each maturity would need to yield to be priced at 100 (par) today, based on secondary-market trading of existing Treasuries. A curve that rises from short to long maturities (short rates lower than long rates) is usually called "normal" or "upward-sloping"; one where short rates sit above long rates is called "inverted." This page just reports the curve's shape as published — it isn't a forecast or a comment on where rates are headed.
Price and yield move opposite each other
A bond pays a fixed coupon set when it's issued. If market yields for similar bonds rise after issuance, a fixed coupon becomes relatively less attractive, so the bond's price has to fall for its effective yield to catch up to the new market rate — and vice versa when market yields fall. That's why "price from yield" and "yield from price" above are really the same calculation run in opposite directions: pick a price, get a yield; pick a yield, get a price. Duration measures how sensitive a given bond's price is to that seesaw — longer maturities and lower coupons generally mean higher duration, i.e. more price movement per point of yield change.
Worked example
Take a 10-year Treasury-like bond with a $1,000 face value and a 5% annual coupon rate, paid semi-annually. Using the 10-year par yield above (5.17%) as the discount rate in "Price from yield," the bond prices at just under $1,000 — a small discount, because its 5% coupon is a little below the 5.17% yield investors currently demand for that maturity. If the 10-year yield instead rose to, say, 6%, the same bond's price would fall further below $1,000, since new bonds could now be bought paying that higher 6% without the price discount. Try both scenarios in the "Price from yield" calculator above by changing only the yield field.
Frequently Asked Questions
Is this Treasury yield curve live?
No. It's the official end-of-day par yield curve for the date shown, published once per US business day by the Treasury. For the current date's rates, follow the source link above to home.treasury.gov directly.
What's the difference between "par yield" and "yield to maturity"?
They're closely related. A par yield is the coupon rate that would make a bond of that maturity trade at exactly its face value (100) right now; yield to maturity is the total return an investor gets holding any specific bond (at whatever price and coupon it actually has) to maturity. For a bond trading exactly at par, the two are the same number.
Does fin·calc recommend buying or selling any bond?
No. This page is reference data and calculators only — it doesn't rate, rank or recommend any security, and isn't a comment on interest-rate direction.