How to Choose a Sports Odds API: 10 Things to Check

The best sports odds API for your product covers your bookmakers and markets, delivers live prices at the speed you need, and keeps limits and costs predictable as you grow. This checklist turns that into ten things you can verify in a day, with the requests to make and a scoring table to copy.

The examples use PulseScore's API and published limits; swap in the endpoints of any provider you are evaluating. New to odds data? Start with what a sportsbook API is.

1. Does it cover your bookmakers and regions?

Start from your users, not from a headline count. List the books they actually bet with, by region: UK books such as Bet365, Paddy Power and Sky Bet; US books such as DraftKings, FanDuel and BetMGM; Australian books such as TAB and Sportsbet AU; and European books such as Betano, Winamax or Sisal.

Then check the exact edition, because one brand often runs separate books per country. PulseScore, for example, carries BetMGM for the US, the UK and the Netherlands, Winamax for France, Germany and Spain, and Ladbrokes for the UK and Australia as separate sources. If you need exchanges or prediction markets, check those too: back and lay prices with liquidity, or last price and bid/ask from Polymarket and Kalshi.

At PulseScore one key covers 60+ bookmakers, and the live availability page shows every book with its sports and live coverage, refreshed hourly.

2. Are the sports and markets deep enough?

"Soccer" can mean a match-result price on five top leagues or hundreds of markets on a second division. Check the leagues and the markets per event you need (handicaps, totals, corners, cards, player props, outrights), and sample fixtures at different distances from kick-off: many books publish their deepest boards only in the last days before a match.

A quick way to measure depth is to pull one page of a pre-match board and count the markets on each event:

import requests

API_KEY = "YOUR_API_KEY"
BASE = "https://api.pulsescore.net/api/fanduel"  # swap in any bookmaker prefix

resp = requests.get(
    f"{BASE}/soccer/events",
    headers={"X-Secret": API_KEY},
    params={"limit": 30},
    timeout=10,
)
resp.raise_for_status()
for event in resp.json()["events"]:
    kinds = {m.get("canonicalMarket") or m["rawName"] for m in event["markets"]}
    print(f'{event["home"]} vs {event["away"]}: {len(event["markets"])} markets, {len(kinds)} types')

Run it on every book you care about, and again a day before a big fixture. PulseScore covers 35+ sports, from soccer and tennis to darts, padel and Australian rules, but each bookmaker carries only what it publishes.

3. How fresh are live odds, really?

"Real time" means different things to different providers, so ask three questions: how often does the feed update, how does it reach you, and how long after the bookmaker's change does the update arrive?

For reference: PulseScore's live WebSocket pushes every in-play event for one bookmaker and sport about once a second, and the Stream API batches changes once a second per stream, so a delta typically arrives 1 to 2 seconds after the bookmaker's write. That suits odds comparison, live widgets and most models, but it is not a sub-second feed; if your edge depends on being first to a price, measure end to end before you commit.

Two measurements settle it. Watch a live match on the bookmaker's site next to the feed for ten minutes and note when suspensions and price moves appear on each. Then log how old each frame is when it reaches you; WebSocket frames carry a timestamp in milliseconds:

import asyncio
import json
import time

import websockets  # pip install websockets

URL = "wss://api.pulsescore.net/api/v3/bet365/ws/live?key=YOUR_API_KEY&sport=soccer"


async def main():
    async with websockets.connect(URL, max_size=None) as ws:
        async for raw in ws:
            msg = json.loads(raw)
            if msg.get("type") == "connected":
                print("plan:", msg["plan"], "| sports:", ", ".join(msg["validSports"]))
                continue
            age_ms = time.time() * 1000 - msg["timestamp"]
            print(f"{msg['count']} live events, frame age {age_ms:.0f} ms")


asyncio.run(main())

Frame age measures delivery from the server to you (keep your clock synced with NTP); the side-by-side check measures the whole chain from the bookmaker.

4. Which delivery methods does it offer?

Match the delivery method to the job:

• REST polling for pre-match boards, batch jobs and prototypes. Available on every PulseScore plan.
• WebSocket push for the live board of one bookmaker and sport: a frame about every second, no polling loop. PRO and above.
• Delta streams for many bookmakers and sports on one socket: each board once, then only what changed. PRO and above, in beta.

Then check bandwidth, because it drives your infrastructure bill. With Accept-Encoding: gzip a PulseScore REST board is 6 to 14 times smaller on the wire. Streams use permessage-deflate (6 to 9 times smaller): a live soccer stream of one bookmaker runs at roughly 50 to 150 KB/s uncompressed, while the first snapshot of a large bookmaker's pre-match soccer board is 20 to 450 MB. The REST vs WebSocket vs delta streams comparison has code for all three.

5. Is the schema normalized across bookmakers?

An aggregator is only as useful as its schema. Look for the same envelope and paths on every book, normalized market, period and outcome fields with the bookmaker's raw label kept as a fallback, decimal odds as numbers, and the line of a total or handicap as its own field.

The test: point the depth script from step 2 at a second bookmaker prefix and change nothing else. If that needs a per-book branch, every book you add will need one too. Event ids are per bookmaker at PulseScore, so cross-book products still match events on teams and start time; the odds comparison tutorial shows how.

6. Does it handle racing properly?

Race cards are a different shape from match boards: runners instead of markets, each-way terms, and prices that fill in as the off approaches. Check the regions covered (UK and Irish, Australian, French), harness and trotting, jockey and trainer on each runner, fractional and decimal prices, and whether races can be pushed rather than polled.

PulseScore serves race cards at /horse-racing/races and /greyhounds/races on racing books (Bet365 puts horse racing under /sports/horse-racing/races), and the Stream API pushes them with kinds=racing. The horse racing odds API guide covers the race schema.

7. Can you get results and settlement?

If you settle bets, grade predictions or back-test models, you need finished events, not just odds. Check how long results are kept, whether they carry period scores and statistics, whether the bookmaker's own settlement of each selection is exposed, and how you filter them.

PulseScore serves /results on 20+ bookmakers, kept for up to 30 days depending on the book, with final scores, period breakdowns and, on some books, the settlement of each selection. Each bookmaker's Swagger page lists its results filters.

8. How are rate limits counted?

Rate limits shape your architecture, so read them closely. Are they counted per key, per endpoint or per bookmaker? Is there a monthly quota on top? What happens at the limit: a 429 with a retry hint, a silent drop or a ban? Do responses show how much headroom is left?

PulseScore counts limits per bookmaker: a PRO key can make 1 req/sec to each bookmaker, so polling five books at that pace stays inside the plan. Every successful response carries X-RateLimit-Limit, X-RateLimit-Remaining and X-RateLimit-Reset; over the limit you get HTTP 429, and ten rejections within ten seconds on one bookmaker pause the key for 60 seconds, with a Retry-After header. Back off on the first 429 and the pause never happens.

Live sockets are budgeted per bookmaker as well, shared between the WebSocket feed and delta streams. The API documentation spells out every limit and error code.

9. Is the pricing predictable?

Check what a plan actually includes (every bookmaker or a subset, live data, results), how overage works, whether there is a free tier or a trial, and what longer terms cost. Per-request billing and per-bookmaker add-ons make costs harder to forecast than a flat monthly tier.

At PulseScore every plan includes every bookmaker, results and deep links; plans differ only in requests, rate and live connections. BASIC is free, STARTER costs €20/mo, PRO €79/mo, MAX €149/mo and ULTRA €249/mo. PRO on monthly billing has a 7-day free trial, and 6- and 12-month terms include 1 month free and 3 months free. Details are on the pricing page.

10. Are the docs, status page and reconnect rules good enough?

Check the docs before the data: every endpoint and field described, error and close codes with what to do about each, copy-paste examples, and a way to try requests without writing code. A status page tells you whether a gap is yours or the provider's. For push feeds, read the reconnect rules too: what happens to your socket when the provider deploys, whether you can resume after a drop without reloading every board, and which close codes mean stop.

PulseScore publishes a Swagger page per bookmaker (https://api.pulsescore.net/api/{bookmaker}/doc), the availability page, and documented HTTP errors and WebSocket close codes. A Stream API client that reconnects with its last sequence number within 120 seconds resumes without a snapshot; after one of our deploys that reconnect was measured at about 0.35 seconds. The Stream API documentation lists every rule.

A one-day evaluation plan

1. Morning: get a free key and pull /live-events and one pre-match board from the two or three books you need. Check compression and the rate-limit headers.
2. Midday: run one parser across those books, count markets per event and note any missing canonical values.
3. Afternoon: during live matches, compare suspensions and price moves with the bookmaker's site; on a PRO trial, connect a WebSocket or a delta stream and log frame ages.
4. Evening: query results for the matches you watched, and confirm your client backs off on a 429 and reconnects cleanly after a dropped socket.

The header check is one command; look for Content-Encoding: gzip and the three X-RateLimit headers:

curl --compressed -sD - -o /dev/null \
  -H "X-Secret: YOUR_API_KEY" \
  "https://api.pulsescore.net/api/v3/bet365/live-events?sport=soccer"

A scoring table to copy

Weight each row by how much it matters to your product (1 to 3), score each provider from 0 to 5 and multiply. A weight-3 row that scores below 3 is usually a deal breaker, whatever the total says.

| Criterion                    | Weight (1-3) | Provider A (0-5) | Provider B (0-5) |
|------------------------------|--------------|------------------|------------------|
| Bookmakers and regions       |              |                  |                  |
| Sports and market depth      |              |                  |                  |
| Live freshness               |              |                  |                  |
| Delivery and bandwidth       |              |                  |                  |
| Schema normalization         |              |                  |                  |
| Racing                       |              |                  |                  |
| Results and settlement       |              |                  |                  |
| Rate limits                  |              |                  |                  |
| Pricing and free tier        |              |                  |                  |
| Docs, status and reconnects  |              |                  |                  |
| Weighted total               |              |                  |                  |