Treasury Yields API
US Treasury yields as JSON, no API key: the daily par yield curve (1M to 30Y), real yields (TIPS), T-bill rates and long-term rates, with 10Y-2Y, 10Y-3M, 30Y-5Y and 2Y-3M spreads, an inversion flag, day-over-day change in basis points and full history since 1990. Modes: latest, one date (nearest previous business day on holidays), history range (daily, weekly or monthly), spreads, and inversion periods. Source: U.S. Department of the Treasury (public domain). Monitor mode returns only new business days.
Example request
curl -X POST https://radarbg.com/v1/treasury-yields-api \
-H "X-API-Key: YOUR_KEY" -H "Content-Type: application/json" \
-d '{"mode": "history", "curve": "nominal", "frequency": "daily", "limit": 1000}'
Answer: {"ok": true, "count": N, "items": [...], "usage": {...}}. Failed calls are not counted.
Inputs
| Field | Type | Description |
|---|---|---|
mode | string | latest = the newest yield curve; date = one day (a holiday or weekend returns the previous business day and says so); history = every business day between Start and End date; spreads = spread time series only; inversion = periods when 10Y-2 |
curve | string | nominal = daily par yield curve (1M-30Y, since 1990); real = real yield curve / TIPS (5Y-30Y, since 2003); bills = T-bill bank discount and coupon equivalent rates (since 2002); longterm = long-term composite and 20Y CMT (since 2000). Sprea |
date | string | For mode date: the day you want, YYYY-MM-DD, for example 2024-03-15. |
startDate | string | For history, spreads and inversion: first day, YYYY-MM-DD. Default 30 days before End date. Max range 40 years. |
endDate | string | For history, spreads and inversion: last day, YYYY-MM-DD. Default today. |
maturities | array | Optional filter, for example 2Y, 10Y, 3M, 30Y. Empty = every maturity of the curve. |
frequency | string | For history and spreads: daily (every business day), weekly (last business day of each week) or monthly (last business day of each month). |
limit | integer | Maximum rows returned (newest kept when the range is longer). Between 1 and 20000. |
onlyNew | boolean | Return only business days newer than the last run with this Monitor ID. Schedule it daily to get each new Treasury curve once. |
monitorId | string | Name of the watch for only-new mode, for example my-dashboard. Each Monitor ID keeps its own last date. |
Price
Included in every plan: 100 calls a month free, then from €9 a month for 3,000 calls across all APIs.