# yfin Docs

> yfin is a hosted Yahoo Finance API with Python and TypeScript SDKs, yfinance-compatible Python calls, OpenAPI schemas, and public rate limits.

## Start Here

- [Getting Started](https://docs.yfin.dev/) - Install yfin and make first requests.
- [Quickstart](https://docs.yfin.dev/quickstart) - Shortest path from install to quote/history data.
- [REST API](https://docs.yfin.dev/rest-api) - Base URL, auth headers, response envelope, and direct HTTP examples.
- [API Reference](https://docs.yfin.dev/api-reference) - Interactive endpoint reference generated from OpenAPI.
- [OpenAPI JSON](https://api.yfin.dev/v1/openapi.json) - Machine-readable API contract.

## SDKs

- [Python SDK](https://docs.yfin.dev/python-sdk) - PyPI package, yfinance-compatible import, low-level client, errors.
- [TypeScript SDK](https://docs.yfin.dev/typescript-sdk) - npm package, TypeScript and JavaScript examples, runtime support.

## Concepts

- [Symbols](https://docs.yfin.dev/concepts/symbols) - Yahoo Finance-style symbols, regions, asset types, search, and lookup.
- [Data Freshness](https://docs.yfin.dev/concepts/data-freshness) - Quote freshness, delayed data, market sessions, and refresh behavior.
- [Historical Prices](https://docs.yfin.dev/concepts/historical-prices) - Ranges, intervals, candles, and chart response shape.
- [Adjusted Prices](https://docs.yfin.dev/concepts/adjusted-prices) - Adjusted close, dividends, splits, and yfinance compatibility.
- [Market Hours & Timezones](https://docs.yfin.dev/concepts/market-hours-timezones) - Market state, sessions, and timestamp handling.
- [Missing Data](https://docs.yfin.dev/concepts/missing-data) - Nulls, empty results, unsupported symbols, and unavailable fields.
- [Financial Fields](https://docs.yfin.dev/concepts/financial-fields) - Common quote and fundamentals field meanings.

## Guides

- [Quotes](https://docs.yfin.dev/guides/quotes) - Fetch latest quote data for one or more symbols.
- [Historical Charts](https://docs.yfin.dev/guides/historical-charts) - Fetch chart candles and historical prices.
- [Options Chains](https://docs.yfin.dev/guides/options-chains) - Fetch expirations, calls, puts, and underlying quote data.
- [Fundamentals](https://docs.yfin.dev/guides/fundamentals) - Fetch company profile, valuation, and financial statement data.
- [Screeners](https://docs.yfin.dev/guides/screeners) - Discover and run security screeners.
- [AI Agents](https://docs.yfin.dev/guides/ai-agents) - Use yfin from coding agents and LLM tools.

## Reference

- [Errors](https://docs.yfin.dev/errors) - Error shape, status codes, retry behavior, and SDK exceptions.
- [Rate Limits](https://docs.yfin.dev/rate-limits) - Public request limits by tier.
- [Versioning](https://docs.yfin.dev/versioning) - API compatibility expectations.
- [yfin vs yfinance](https://docs.yfin.dev/yfin-vs-yfinance) - Direct comparison.
- [Migrate from yfinance](https://docs.yfin.dev/yfinance-compatibility) - Compatibility map and migration checklist.