Finnhub review

Finnhub is a hosted financial-data API, not a database you install in your own stack. It exposes RESTful APIs and WebSocket feeds for stocks, currencies and crypto, alongside fundamental and alternative financial data. An application can request market prices or company data from Finnhub and consume streaming updates over a WebSocket connection.

The catalog extends beyond quotes. It includes company financial statements, analyst estimates, ETF and mutual-fund profiles and holdings, index constituents, news and social sentiment, ESG data, congressional trading, Senate lobbying and technical-analysis indicators. Finnhub says its global company financial statements go back 30+ years. It lists real-time US stock data and delayed or end-of-day international market data, with specific market products including delayed FINRA Trace corporate bonds and delayed LSE data.

In a typical stack, Finnhub sits behind a service that fetches or streams financial data for a research tool, trading application or charting interface. The application remains responsible for its own storage, business logic and handling of unavailable or delayed data.

The documented integration surface on Finnhub’s homepage is a REST API plus WebSocket feeds. The site links to API documentation and an API-key registration flow. The homepage describes real-time stock, forex and cryptocurrency access, alongside fundamental and alternative-data endpoints. It also lists Excel and Google Spreadsheet integrations, Finnhub Connect and a Widget product.

The homepage does not name programming-language SDKs or a CLI. A Reddit commenter points to a Finnhub Stock API PHP client, but that is a community reference rather than a complete official SDK list. Confirm supported SDKs and current language versions in Finnhub’s documentation before choosing a client library. The API key and the REST/WebSocket interfaces are the integration points to plan around; the vendor’s documentation should guide endpoint parameters and response handling.

Finnhub describes technical-analysis support for indicators, support and resistance levels, pattern recognition and aggregate signals. Before implementation, map the endpoints you need to your subscription: data coverage and request limits differ by plan, and some datasets, including earnings-call transcripts, have separate terms.

Finnhub’s Free plan costs $0 per month and includes 60 API calls per minute, US coverage and 50 WebSocket symbols. It also includes one year of company news with real-time updates and four quarters of EPS surprises. That is enough to evaluate a US-focused integration, but it is not a general global-data allowance.

All-In-One is listed at $3,500 per month with annual billing. It includes 900 market API calls per minute, 300 fundamental API calls per minute, global fundamental and estimates coverage, 30+ years of annual and quarterly financial statements, and unlimited WebSocket symbols. Monthly billing is not listed. The plan is a fixed subscription with stated rate limits; Finnhub does not publish overage pricing in the published plan details, so ask what happens when a workload exceeds its limits.

Earnings-call transcripts are excluded from All-In-One. Finnhub says to contact it to add transcripts, but does not publish the price. Budget and procurement should account for that add-on and confirm the exact market coverage your application needs before committing to annual billing.

Finnhub is offered as a hosted API service. Its homepage does not list an open-source license or a self-hosted edition, so teams should not treat it as a component they can run inside their own infrastructure. Ask Finnhub about the applicable data-use terms, redistribution rights and any retention restrictions before storing or serving its data to customers.

The REST and WebSocket interfaces give you a conventional integration surface, but changing providers still means replacing endpoint calls, authentication and data mappings. Finnhub’s homepage does not describe a bulk export or migration service for its datasets. Your own application can store data it has retrieved only to the extent allowed by Finnhub’s terms; confirm those rights and the available export options with the vendor.

To reduce switching work, isolate Finnhub behind an internal data-access layer, normalize symbols and fields in your own schema, and avoid making vendor-specific response shapes part of application logic.

Rate limits are a primary production constraint: the Free plan lists 60 API calls per minute, while All-In-One lists separate limits of 900 market and 300 fundamental API calls per minute. Free also caps WebSocket use at 50 symbols; All-In-One lists unlimited WebSocket symbols. Build queueing, caching and reconnect handling around the limits and confirm any additional restrictions in the API documentation.

Finnhub advertises 99.99% uptime with an SLA available for enterprise clients. That is a vendor claim, not a guarantee for every plan; ask what the SLA covers, how incidents are reported and what support response commitments apply to your account. The homepage lists a technical-support email address but does not give response-time or security and compliance details. Review those terms with Finnhub before using the API for regulated or customer-facing workloads.

Reddit feedback is mixed. One thread includes a user report of non-US symbols becoming unsupported and concerns about price and dataset changes. Verify your required symbols and endpoints on the intended plan, and keep a fallback path for data that is critical to production.