Comprehensive fixed income coverage including US Treasury yields, corporate bond spreads, municipal bonds, and sovereign debt. Yield curves, credit ratings, maturity profiles, and coupon schedules for institutional-grade fixed income analytics.
What shipped
- /v1/bonds/treasury/yields — US Treasury yield curve (1M to 30Y)
- /v1/bonds/corporate/{cusip} — corporate bond details, yield, spread
- /v1/bonds/indices — investment-grade and high-yield index levels
- Duration, convexity, and spread-to-benchmark calculations
Endpoint
Primary path: /v1/bonds/treasury/yields. Auth is a Bearer token. Responses are typed JSON documented in OpenAPI 3.0.3.
curl -H 'Authorization: Bearer YOUR_KEY' \
'https://api.eulerpool.com/v1/bonds/treasury/yields'Authentication
Send Authorization: Bearer YOUR_KEY. Keys are created at register in under a minute. Official SDKs take the key in the constructor; Excel stores it in the add-in settings. There is no key-in-query-string mode — do not paste tokens into public notebooks.
Primary route for this article: /v1/bonds/treasury/yields. Docs: /financial-data-api/fixed-income-data.
Coverage and freshness
Eulerpool maps 100,000+ securities across 90+ exchanges. bond and fixed income data API rides that same reference layer — identifiers resolve through ticker, name, ISIN, or CUSIP via search, so a European name is not a dead end. History depth depends on the source: prices and macro go back 100+ years, 1-minute bars to 2010, 13F to 2013.
Paid plans can stream quotes over WebSocket; the free plan uses REST with a 15-minute delay on real-time equity fields. Fundamentals, ownership, and calendars are identical on every plan. Rate-limit headers ship on every response. Batch routes (up to 100 symbols) count as one request.
Why it exists
Most teams land here after fighting Yahoo Finance scrapers, Alpha Vantage’s 25-request/day ceiling, or a Polygon bill that ignored fundamentals. Eulerpool is a licensed bond and fixed income data API with statements, estimates, filings, and macro on the same key — and a terms of service you can actually show legal.
Deep comparisons live here: vs Alpha Vantage, vs Polygon, Yahoo Finance alternative, best stock market APIs in 2026.
Who uses it
- Quant research — pandas/R dataframes, point-in-time fields, 20+ years of history where the source publishes it.
- Fintech apps — watchlists, screeners, and portfolio views without relicensing Bloomberg for every customer.
- AI agents — typed JSON and a native MCP server so models stop inventing numbers for bond and fixed income data API.
- Spreadsheets — the Excel and Google Sheets add-in covers the same endpoints as REST.
Get started
Create a free key at eulerpool.com/developers/register — no credit card, 100,000 requests/month. Then read the bond and fixed income data API docs and ship.
Every day’s drop is listed on the Financial Data API changelog. Same data powers the Eulerpool terminal 500,000+ investors already use — the API is that database with a key in front of it.