A plain-English answer, a real response, and what people actually build with the prices.
An odds API is a service that fetches prices from many sportsbooks, exchanges and prediction markets, puts every price in the same shape, and returns it as JSON over HTTP. Instead of opening a dozen betting sites and reading numbers off a page, a program sends one request and gets back every book's price for a fixture in a response it can parse directly.
The API itself does not judge, recommend or place anything. It answers one question: what is each book currently showing for this fixture, and when did it last confirm that price.
A real response to GET /v1/sports/{sport}/odds, taken from the API's own OpenAPI description, not typed by hand.
[
{
"id": "soccer:crystalpalace-nottinghamforest:2026-10-11",
"sport_key": "soccer",
"sport_title": "Soccer",
"commence_time": "2026-10-11T13:00:00.000Z",
"is_live": false,
"status": "scheduled",
"home_team": "Crystal Palace",
"away_team": "Nottingham Forest",
"bookmakers": [
{
"key": "betmgm",
"title": "BetMGM",
"link": "https://sports.nj.betmgm.com/en/sports/events/crystal-palace-nottingham-forest-2:7865814",
"last_update": "2026-10-10T22:06:51.003Z",
"markets": [
{
"key": "spreads",
"last_update": "2026-10-10T22:06:51.003Z",
"outcomes": [
{
"name": "Nottingham Forest",
"price": 145,
"point": -0.5,
"main": true
},
{
"name": "Crystal Palace",
"price": -210,
"point": 0.5,
"main": true
}
]
}
]
}
],
"unmatched_bookmakers": []
}
]Described factually, as things people build. None of it is endorsed or promised to work.
37 sportsbooks, 6 exchanges and 3 prediction markets, all reduced to the same fields: fixture, bookmakers, markets, outcomes. A prediction market like an exchange is priced the same way a sportsbook is, not bolted on as a special case.
last_update is present on every price and can be null. A null value means we do not yet measure a fetch time for that book, and it is never an estimate.
Every book is available on every plan, with no regional gating and nothing to configure to see it.
When a book returns nothing for a fixture, unmatched_bookmakers names it, so a gap never looks like a missing price.
Free plan: 1,000 requests a month, every book.