Odds API by market / MLB
MLB Walks API
Live batter_walks odds across every book that posts it, in one REST call — and, unlike any other odds API, every one of those outcomes settled against the official result once play ends.
No credit card. 1,000 requests / day on the free tier.
What MLB walks is
Bases on balls drawn by one hitter.
How we settle it. Graded against the batting stat group's walks column.
Every number on this page is measured against the live API, never copied from a spec sheet. Last measured 8 September 2026.
Books posting MLB walks
Measured live, not listed from a spec. Coverage moves — a book that has not put its board up yet will not appear until it does, which is exactly what this list is for.
Line shopping across all of them is one request — every book arrives in the same bookmakers array, not one call per book. Add ?bookmakers= to narrow it, or use /best-line for the best price per line already ranked.
Recently settled MLB walks outcomes
These are real rows out of the API, not an illustration. Each one was a price on a board before the event and carries the actual figure it was graded against afterwards. No other odds API returns that last column — they stop at the price.
14,753 walks outcomes settled in the last 4 days across 9 books. The 12 most recent:
| Player | Bet | Actual | Result |
|---|---|---|---|
| Alejandro Kirk | Over 0.5 | 0.0 | lost |
| Brett Bateman | Over 0.5 | 1.0 | won |
| Carlos Cortes | Over 0.5 | 0.0 | lost |
| Alejandro Kirk | Over 0.5 | 0.0 | lost |
| Brett Bateman | Over 0.5 | 1.0 | won |
| Carlos Cortes | Over 0.5 | 0.0 | lost |
| Charles McAdoo | Over 0.5 | 0.0 | lost |
| Donovan Walton | Over 0.5 | 1.0 | won |
| George Springer | Over 0.5 | 0.0 | lost |
| Vladimir Guerrero Jr. | Over 0.5 | 0.0 | lost |
| Vladimir Guerrero Jr. | Under 0.5 | 0.0 | won |
| Charles McAdoo | Over 0.5 | 0.0 | lost |
Over/Under split, last 4 days
The Over won 22.6% of 6144 decided walks lines (1389 over, 4755 under). Computed from the settled rows themselves, scoped to MLB only.
Read off 6,612 Over legs out of 14,753 settled outcomes on this market. The rest are Unders and milestone legs (“1+”, “2+”) that some books price here too, and a threshold rung is not an Over.
A few days of one market describes a few days — it is not an edge. Pull the full history through /exports/resolved-props for a sample worth modelling on.
Live response
Captured from the real endpoint on Cleveland Guardians @ Baltimore Orioles, trimmed to one book and three outcomes so the shape stays readable. The full response carries every book and every line, alternates included, in the same call.
{
"home_team_key": "orioles",
"away_team_key": "guardians",
"home_team_id": "mlb:110",
"away_team_id": "mlb:114",
"id": "203340",
"sport_key": "baseball_mlb",
"home_team": "Baltimore Orioles",
"away_team": "Cleveland Guardians",
"commence_time": "2026-09-08T22:35:00Z",
"live": false,
"last_update": "2026-09-08T13:56:13.244786Z",
"merged_from_event_ids": null,
"bookmakers": [
{
"key": "draftkings",
"title": "DraftKings",
"last_update": "2026-09-08T13:56:07.104599Z",
"link": null,
"app_link": null,
"pregame_only": false,
"book_event_id": null,
"markets": [
{
"key": "batter_walks",
"description": "Angel Genao Walks",
"last_update": "2026-09-08T13:55:53.677192Z",
"period": null,
"suspended_at": null,
"team": null,
"outcomes": [
{
"name": "1+ Walks",
"description": "Angel Genao",
"price": 233,
"point": null,
"book_updated_at": null,
"book_version": null,
"payout_multiplier": null,
"dfs_odds_type": null,
"last_change_at": "2026-09-08T07:58:58.250594Z",
"last_seen_at": "2026-09-08T13:55:53.677192Z",
"liquidity": null,
"liquidity_updated_at": null,
"line_gap": null,
"book_outcome_id": null,
"outcome_id": null,
"player_id": "mlb:694197"
}
]
}
]
}
]
}The response shape is the-odds-api compatible — events, bookmakers, markets, outcomes — so migrating is usually a base URL change.
Try it
1. List MLB events to get an event id:
curl "https://api.prop-line.com/v1/sports/baseball_mlb/events?apiKey=YOUR_API_KEY"2. Pull walks for one game across every book — this exact URL works right now:
curl "https://api.prop-line.com/v1/sports/baseball_mlb/events/203340/odds?apiKey=YOUR_API_KEY&markets=batter_walks"3. After the game, get the graded outcomes with the actual stat:
curl "https://api.prop-line.com/v1/sports/baseball_mlb/events/203340/results?apiKey=YOUR_API_KEY"Steps 1 and 2 run on the free tier. Step 3 — prop resolution — starts on Hobby at $9/mo. See pricing.
Get your free MLB odds API key
1,000 requests / day. No credit card. The same key covers every sport and every market — not just this one.
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