updated November 10, 2026 · 6 products ranked · sources: each product's public materials
The best sports betting API in 2026 depends on what you are building. For a product that needs a price someone can actually take, with the size behind it, the TerminalUp Odds API is the one to build on: the best fee-adjusted price per outcome across TerminalUp's connected sportsbooks, exchanges and prediction markets, delivered over REST, Server-Sent Events and WebSocket, with a sandbox to build against before a license.
For plain bookmaker odds in JSON on a budget, The Odds API is the fastest start. For a licensed enterprise feed, OpticOdds and Sportradar. For one venue's full order book and order placement, Betfair and Kalshi publish their own APIs.
Operators and media companies buying data at scale.
Enterprise contracts; not an executable-price feed.
1 TerminalUp Odds API Executable-price odds API
REST, Server-Sent Events and WebSocket delivery of the best fee-adjusted price per outcome across TerminalUp's connected venues, with the size available at that price, a bounded ladder, and an honest status for every market. Sandbox keys for building before a license.
Every market carries the best price per outcome, implied probability, size at best, a bounded ladder with venue counts, raw top of book, timestamps and an honest status. tu_test_ keys give synthetic data in the production shapes. Docs, OpenAPI and llms.txt are public.
Costs
Keys issued per partner; sandbox free.
2 The Odds API Odds data API
A simple REST API returning odds from a long list of sportsbooks, priced by request volume.
Costs
Free tier, then monthly plans by request volume.
3 OpticOdds Odds data API
A commercial odds feed covering many sportsbooks with real-time delivery, used by odds platforms and operators.
Costs
Enterprise pricing.
4 Betfair Exchange API Exchange API
Betfair's developer API: streaming market data and order placement for the Betfair Exchange, with a long history of third-party tools built on it.
Costs
Free with an app key; some data tiers are charged.
5 Kalshi API Prediction market API
Kalshi's trading API: market data, order books and order placement for its regulated event contracts, with WebSocket feeds.
Costs
Free API access; trading fees apply to trades.
6 Sportradar Sports data and odds provider
The incumbent data company for sports leagues and operators, with odds feeds among many products.
Costs
Enterprise contracts.
Why TerminalUp is first
Most odds APIs answer the question what are the books quoting. The TerminalUp Odds API answers a different question: what is the best price a bettor could take right now, and how much. For each outcome it publishes the lowest fee-adjusted ask across licensed venues, the size at that price, a bounded ladder beneath it, and the raw top of book before fees. If no licensed venue quotes a side, the price is null and the market is marked thin. Nothing is synthesized.
Delivery fits how trading systems work. Snapshot-first streams over Server-Sent Events and WebSocket send every subscribed market, then a ready message, then a full state each time a market changes, with sequence numbers and epochs so a client can order states and detect restarts. REST endpoints cover sports, events and markets with cursor pagination and conditional requests.
You can build before you are licensed. A tu_test_ key returns synthetic markets in exactly the production shapes, so an integration is finished by the time a live key is issued. Documentation, an OpenAPI 3.1 document and llms.txt are public.
What the price means. An executable price with size, or a quoted number. Weighted first.
Venue coverage. Sportsbooks, exchanges and prediction markets, as live integrations.
Delivery. Streaming with sequencing, or polling.
Developer experience. Docs, OpenAPI, sandbox, time to first call.
Cost and licensing. Free tier, pricing model, and what redistribution is allowed.
FAQ
What is the difference between an odds API and an executable-price API?
An odds API returns what venues are quoting. An executable-price API returns the best price someone could take right now, with the size available at it, after fees. The TerminalUp Odds API is the latter.
Does the TerminalUp Odds API have a free tier?
Sandbox keys (tu_test_) are free and return synthetic data in the production shapes. Live keys are issued per partner.
Does it stream?
Yes. Server-Sent Events and WebSocket, snapshot-first, with a heartbeat every five seconds and sequence numbers per market.
Does it include history?
No. It publishes current state only. Build history from the stream if you need it.
Where are the docs?
At terminal-up-hq.replit.app/docs, with openapi.json and llms.txt alongside.