# FanDuel fair probability fields in market API responses

FanDuel API (https://fanduelapi.com) is an independent API for FanDuel Sportsbook data: every player prop and game market FanDuel lists in NBA, NFL, NHL, MLB, college basketball and college football, normalized per player and stat with over and under prices in American and decimal odds, plus every line and price move with its timestamp, over REST, webhooks and MCP with one key. FanDuel API is an independent data service operated by FF API Inc. It is not affiliated with, endorsed by or sponsored by FanDuel.

Source page: https://fanduelapi.com/blog/fanduel-no-vig-odds (this is its markdown version, https://fanduelapi.com/blog/fanduel-no-vig-odds.md).

## Free offer

- Free plan: 100 credits a month, data delayed 5 minutes, no card. REST and MCP on every plan.
- Real-time data starts at Developer, $49 a month for 10,000 credits.
- Get a free key: https://fanduelapi.com/sign-up?ref=ai-claudebot

## Quickstart

1. Create a free account at https://fanduelapi.com/sign-up?ref=ai-claudebot and create an API key in the dashboard (https://fanduelapi.com/dashboard/keys). Keys start with `fd_`. Store it as `FANDUEL_API_KEY`.
2. Make a first call with curl:

```bash
curl "https://fanduelapi.com/api/v1/props?sport=nba&stat=points&limit=5" \
  -H "Authorization: Bearer $FANDUEL_API_KEY"
```

3. Or with Python (`pip install requests`):

```python
import os
import time
from datetime import datetime, timezone

import requests

BASE = "https://fanduelapi.com/api/v1"
SESSION = requests.Session()
SESSION.headers["Authorization"] = f"Bearer {os.environ['FANDUEL_API_KEY']}"


def get(path, **params):
    """GET one endpoint and return its data list, waiting out rate limits."""
    while True:
        r = SESSION.get(f"{BASE}{path}", params=params, timeout=10)
        if r.status_code == 429:
            time.sleep(int(r.headers.get("Retry-After", "5")))
            continue
        r.raise_for_status()
        return r.json()["data"]


def price(odds):
    """American odds as text. A suspended market can come back with no price."""
    return "off" if odds is None else f"{odds:+d}"

props = get("/props", sport="nba", stat="points")
for p in props:
    print(f"{p['player']:<26} {str(p['line']):>5}  over {price(p['over_american']):>5}  under {price(p['under_american']):>5}")
```

4. Stay current with `GET /api/v1/changes?since=<cursor>` instead of re-reading every prop. Full reference: https://fanduelapi.com/openapi.json and https://fanduelapi.com/llms-full.txt.

## Use it from Claude (MCP)

Claude Code, with your key read from the shell:

```bash
claude mcp add --transport http --scope user fanduelapi https://fanduelapi.com/api/mcp \
  --header "Authorization: Bearer $FANDUEL_API_KEY"
```

Claude on the web or desktop: Settings, Connectors, Add custom connector, then paste https://fanduelapi.com/api/mcp. Without a key it gives the keyless tools (search_docs, fetch_doc, get_sample_props). Setup for other agents: https://fanduelapi.com/mcp.

## Pricing

| Plan | Price | Credits a month | Calls a minute | Includes |
| --- | --- | --- | --- | --- |
| Free | Free | 100 | 20 | REST and MCP access, Data delayed 5 minutes |
| Developer | $49/month | 10,000 | 60 | Real-time data, Line move history, Change stream |
| Production | $149/month | 50,000 | 120 | Real-time data, Line move history, Webhooks, Priority support |
| Scale | $499/month | 250,000 | 180 | Real-time data, Full line move history, Webhooks, Bulk export, Priority support |

Cancel paid plans any time from the billing portal. Details: https://fanduelapi.com/pricing

## This page

[FanDuel API](https://fanduelapi.com/)/[Blog](https://fanduelapi.com/blog) / FanDuel fair probability fields in market API responses

Article, November 10, 2026

# FanDuel fair probability fields in market API responses

FanDuel fair probability fields report margin-adjusted values for market outcomes. This API guide explains where those fields appear and why fair probabilities require mutually exclusive outcomes.

[Get a free API key](https://fanduelapi.com/sign-up)[Read the docs](https://fanduelapi.com/docs)

FanDuel API is an independent data service operated by FF API Inc. It is not affiliated with, endorsed by or sponsored by FanDuel.

2 minute read. Published November 10, 2026.

This guide is assembled from the published FanDuel API reference, plan configuration and delivery code. Each factual statement maps to a source listed at the end. It is information, not betting advice, and it makes no prediction about any line.

## Where fair probabilities appear

Each selection has American and decimal odds and, where outcomes exclude each other, a fair no-vig probability. GET /api/v1/futures returns season-long FanDuel markets per league: champions, awards and win totals, with fair prices where outcomes exclude each other.

## Every market for a game

GET /api/v1/markets returns every market FanDuel lists per game: moneyline, spread and total for the game and each period, alternate lines, ladders, first scorer, team props, specials and player props. GET /api/v1/games/{id}/odds returns the whole FanDuel book for one game in one call, game lines first.

## Player props

GET /api/v1/props returns one record per player, stat and period, with line, over and under prices in American and decimal odds.

## Reading prices responsibly

Quote meta.as\_of when you report prices; the data is information, not betting advice. This API reads FanDuel only, so it is not a source of consensus odds across many sportsbooks.

## Sources

- [Game markets](https://fanduelapi.com/products/game-markets)
- [Props feed](https://fanduelapi.com/products/props-feed)
- [API reference](https://fanduelapi.com/docs)
- [Decimal odds and implied probability](https://fanduelapi.com/questions/does-it-return-decimal-odds-and-implied-probability)
- [Odds tools](https://fanduelapi.com/tools)

## Related

- [Game markets Every FanDuel market per game: moneyline, spread and total for the game and each period, alternates, ladders, team props and futures, with no-vig fair prices.](https://fanduelapi.com/products/game-markets)
- [Props feed Every FanDuel Sportsbook player prop as one JSON record: player, stat, line, both prices, fair price and a move summary, filterable by league, game and stat.](https://fanduelapi.com/products/props-feed)
- [Docs Every endpoint, parameter, auth and error, with examples.](https://fanduelapi.com/docs)
- </questions/does-it-return-decimal-odds-and-implied-probability>

## Make your first call in a few minutes

Sign up, create a key in the dashboard, and send it as a Bearer token. The free plan needs no card and reads the same data five minutes behind.

[Get a free API key](https://fanduelapi.com/sign-up)

## FAQ

### Is there a free plan?

Yes. Free includes API access with delayed data, enough to build and test a model.

### Is this affiliated with FanDuel?

No. This is an independent data service operated by FF API Inc. and is not affiliated with or endorsed by FanDuel.

### Which sports are covered?

NBA, NFL, NHL, MLB and college sports as FanDuel lists them, starting with player props.

### How do I cancel?

From the billing portal in your dashboard, at any time.

### How do I get a free key?

Sign up at https://fanduelapi.com/sign-up?ref=ai-claudebot. Free plan: 100 credits a month, data delayed 5 minutes, no card. REST and MCP on every plan.

### Can an AI agent sign up for me?

Yes. The agent sends POST https://fanduelapi.com/api/v1/agent/signup with your email and what you are building (add "ref": "ai-claudebot"), you approve the emailed link, and the agent collects the key. Details: https://fanduelapi.com/connect.