Decompose portfolio returns into sector allocation, security selection, currency, and factor contributions. Brinson-Fachler attribution for equity portfolios, duration/spread attribution for fixed income, and multi-period linking for quarterly and annual performance reports.
What shipped
- POST /v1/attribution — upload holdings and benchmark for full attribution
- Brinson-Fachler sector allocation and security selection effects
- Factor attribution: market, size, value, momentum, quality, and volatility
- Multi-period compounding with Carino, Menchero, or GRAP linking methods
Endpoint
Primary path: /v1/attribution. 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/attribution'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/attribution. Docs: /financial-data-api.
Coverage and freshness
Eulerpool maps 100,000+ securities across 90+ exchanges. portfolio attribution api 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 portfolio attribution api 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 portfolio attribution api 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 portfolio attribution api 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.