Finnhub

What it is

Finnhub is a REST and WebSocket API covering quotes, global fundamentals, analyst estimates and a long tail of alternative data — insider transactions, congressional trading, USPTO patents. The documentation lists 116 endpoints; roughly a quarter are open to a free key.

That free key is generous in an unusual shape: real-time US quotes, live trades over WebSocket for up to 50 symbols, a year of company news with real-time updates, SEC filings, key metrics and as-reported financials. What it will not return is a single OHLC candle, and no tick data either. Finnhub gives away the current price and charges for the history behind it — the reverse of most free tiers, and the thing that catches anyone who assumed a free real-time API would also backfill a chart. Free fundamentals are US-only and thin: standardised statements, dividends, ownership, press releases and executives are all paid rows.

Pricing

Free is 60 calls per minute. Market data then runs Basic at $49.99 a month for 150 calls per minute, Standard at $129.99 for 300, Professional at $199.99 for 900. Watch the billing frequency rather than the monthly figure: Basic and Standard bill quarterly — $149.97 and $389.97 taken up front — and Professional annually at $2,399.88, so none of them is month-to-month. There are no refunds, cancelling by email wants 30 days' notice, and API access is cut the moment a subscription ends.

Fundamentals, estimates, ETFs, bonds and economic data are separate products rather than tiers of this one, and each carries its own price: fundamentals from $50 a month, estimates from $75, economic data $50, bonds $99.99, ETFs from $500, and the All-In-One bundle that carries everything at $3,500. Stacking them buys no headroom — the terms give you one rate limit for fundamental data and one for market data however many plans you hold, and a hard 30 calls per second sits above every plan's per-minute figure.

Data & coverage

Real-time means US. Professional adds TSX, LSE, Euronext and Deutsche Börse, but the footnote matters more than the logos: LSE is delayed 15 minutes and the other international markets are end-of-day. History scales with the tier — 10 years of daily and 1-minute bars on Basic, 25 on Standard, and on Professional 40-plus years of daily bars but 30-plus of 1-minute. Tick history runs 5, 10 and 30-plus years across the same three tiers, and all three include bulk tick download. The WebSocket caps symbols at 50 on the free key and 250 on Basic; Standard and Professional lift the cap.

Integrations

Official client libraries for Python, Go, JavaScript, Ruby, PHP and Kotlin, plus Finnhub's own MCP server for ChatGPT, Claude and Gemini Enterprise. Spreadsheet access runs through Finsheet, a partner plugin sold separately.

Limitations

• No OHLC or tick data on the free tier at all.
• Every self-serve plan is licensed for personal use, including All-In-One at $3,500 a month. Commercial use and redistribution need an Enterprise contract — a call, not a checkout.
• The terms forbid redistributing or sharing access to the data or derived results from it with any third party without written approval, and say a personal plan may not be used by a business even internally.
• You do not qualify for a personal plan at all if you are registered with FINRA, the SEC or the CFTC, if you use the data for your business or sign up under a business name in any industry, or if you deduct the subscription as a business expense. Signing up certifies you as a non-professional subscriber on a form Finnhub files with its data partners.
• No options data anywhere in the API.
• Intraday candles are not split-adjusted; only daily bars are. Quiet backtest errors start here.
• Intraday requests return one month at a time, so a real backfill is a paging loop.
• One WebSocket connection per API key.
• Company news covers North American companies only, on every plan.

Alternatives

Massive (formerly Polygon.io) sells full tick history and flat files for US markets. Twelve Data and EODHD cover more non-US exchanges in real time. Databento is the one to look at when tick data and a redistribution licence are the real requirement.

See the rest of the market data APIs.