REST vs WebSocket for odds data: which should you use?

Polling a REST endpoint or streaming over a WebSocket. How the two approaches differ for bookmaker odds, and how to pick the right one for what you are building.

Guide · Updated June 2026

With a REST API you ask for odds on a schedule. Every few seconds your code sends a request, gets the current prices back, and waits to ask again. That works, but you are always a little behind, and you spend requests checking for changes that have not happened yet. A WebSocket flips this around. You open one long lived connection and the server sends you new odds the moment they are available. No timer, no guessing how often to poll, no wasted calls.

Both are good tools. The right one depends on how fresh your data needs to be and how much you are willing to build. Here is the breakdown.

At a glance

How REST works

You send a GET request to one endpoint with the sport, bookmakers, and market types you want, and you get standardised JSON back. There is nothing to keep alive and nothing to manage. It is the easiest way to get started, and on the free tier it is the only way, since WebSocket is on the paid plans.

The catch is freshness. Your data is only as current as your last request. To stay close to live you have to poll often, and most of those polls come back with prices that have not moved, which spends requests and credits for nothing. We cover the endpoint in detail in the guide to pulling odds over REST.

How WebSocket works

You open one connection and subscribe to the sports and bookmakers you care about. From then on, every time prices refresh for those sports, the server pushes the new odds to you. The push is event driven, it fires when a scrape cycle completes for that sport, so you get the update as soon as it lands rather than on a fixed clock. The data in each push is identical in shape to the REST response, so your parsing code does not change. The full walkthrough is in the WebSocket streaming guide.

Which should you use?

Reach for REST if

• You only need a snapshot now and then, or run a scheduled job a few times a day.
• You are prototyping, learning the data, or on the free tier.
• Being a little behind on price changes is fine for your use case.
• You want the simplest possible integration with nothing to keep alive.

Reach for WebSocket if

• You are building an arbitrage scanner or a positive expected value finder, where stale prices mean missed or false opportunities.
• You track line movement and want every change as it happens.
• You run anything live, where seconds matter.
• You are polling REST so often that you are spending more on checking than on real changes.

You do not have to choose forever

Because both deliver the same standardised JSON, the common path is to start on REST while you build and learn the data, then switch to the WebSocket feed once you need real time updates. The model your code works with does not change, only how the data arrives. Many production setups use both: WebSocket for the live feed, REST for backfilling or one off lookups.

A note on credits

Both use the same credit formula, market_types × ceil(bookmakers / 5). On REST you pay per request. On WebSocket you pay per push, and only when a push actually contains data. In practice a WebSocket feed can use credits more efficiently, because you are charged when prices change rather than every time you poll to check. Either way you are only ever charged when data is returned.

Ready to build? Start with the REST guide or the WebSocket guide, or read the full API documentation.