An NFL player props API

Quick answer: GridIron Data Pro ($29 a month or $249 a year) has three betting endpoints. /props turns a player stat line, such as 245.5 passing yards, into P(over), P(under) and a fair no-vig price, with the model's backtest. /defense ranks what each defense allows to QBs, RBs, WRs and TEs. /schedule adds the spread, total, moneylines and implied team points. GridIron does not sell sportsbook prop lines; you bring the line you want priced.

Written by Aaron VanSledright, founder of 45Squared, which builds and runs GridIron Data · Updated October 27, 2026

Plan: Pro
Price: $29/mo
Requests: 50,000/mo
Prop stats: 11

How do I price a player prop?

Send the player, the stat and up to 10 lines. Stats: pass_yds, pass_td, pass_att, pass_cmp, pass_int, rush_yds, rush_att, rush_td, rec, rec_yds and rec_td, for QBs, RBs, WRs and TEs.

curl -H "x-api-key: YOUR_PRO_KEY" \
  "https://api.gridirondata.com/api/v1/props?player_id=Drake%20Maye%23QB&stat=pass_yds&line=245.5"

{
  "player_id": "Drake Maye#QB",
  "espn_player_id": 4431452,
  "team": "NE",
  "week": 8,
  "stat": "pass_yds",
  "injury_status": "ACTIVE",
  "available": true,
  "game": {"opponent": "NYJ", "home": true, "implied_team_points": 26.5, "odds": {"...": "..."}},
  "projection": {
    "mean": 249.3,
    "sd": 58.1,
    "distribution": "normal",
    "season_projection_per_game": 239.03,
    "games_played": 7,
    "season_average": 262.4
  },
  "lines": [
    {"line": 245.5, "p_over": 0.526, "p_under": 0.474, "p_push": 0,
     "fair_odds_over": -111, "fair_odds_under": 111}
  ],
  "model": {"backtest": {"n": 2135, "brier": 0.172, "brier_base_rate": 0.25, "calibration": ["..."]}},
  "disclaimer": "Model estimate, not betting advice. ..."
}

Compare fair_odds_over with the price your book offers. The mean blends the player's season projection with his own games this season, and the spread is fitted per position and stat on every 2025 and 2026 game. Every response includes the stat's walk-forward backtest (Brier score, log loss and a calibration table), so you can judge the model before you use it. Players who are OUT, on IR or on bye get p_over 0. You can also look a player up by espn_id, the id many odds feeds use.

How do I get defense vs position?

curl -H "x-api-key: YOUR_PRO_KEY" \
  "https://api.gridirondata.com/api/v1/defense?position=WR&last=4"

{
  "season": "2026",
  "scoring": "ppr",
  "weeks": [4, 5, 6, 7],
  "position": "WR",
  "defenses": [
    {
      "team": "MIA",
      "rank": 1,
      "games": 4,
      "fantasy_points_allowed_per_game": 46.2,
      "per_game": {"targets": 24.5, "rec": 16.8, "rec_yds": 221.3, "rec_td": 1.5}
    }
  ],
  "rank_meaning": "1 = allows the most fantasy points per game to this position",
  "source": "ESPN box scores"
}

Rank 1 allows the most, the best matchup for that position. Stat lines come from ESPN box scores for every game since 2025, loaded after each week's games.

Where are spreads, totals and implied team points?

On Pro, each /schedule game has an odds object, refreshed daily until kickoff. A final game keeps the last line seen before kickoff, which makes closing lines easy to backtest.

"odds": {
  "provider": "DraftKings",
  "spread_home": -3.0,
  "over_under": 47.5,
  "home_moneyline": -155,
  "away_moneyline": 130,
  "implied_home_points": 25.25,
  "implied_away_points": 22.25,
  "captured_at": "2026-10-23T14:00:05Z"
}

What the API does not do

It does not sell or scrape sportsbook player-prop lines. Bring the line you want priced.
It has no live in-game stats or in-play odds.
It does not place bets or give picks. Probabilities are a model estimate, not betting advice.

Sports betting is legal only in some places and only for adults, 21 and over in most US states. Follow your local laws. If gambling stops being fun, call 1-800-GAMBLER.

What else comes with Pro?

Pro is $29 a month or $249 a year with 50,000 requests a month at 100 a minute. Besides the three betting endpoints it adds per-stat projections on every /projections/{week} row (pass_yds, rec, rush_yds and the rest), the injury changes feed and signed injury webhooks, so a model can re-price within minutes of a status change. Everything in Basic is included. A step-by-step script is in Price NFL player props with a probability API.

Frequently asked questions

Does GridIron Data provide sportsbook player prop lines?

No. It prices the line you send: P(over), P(under), P(push) and fair no-vig odds. Game spreads, totals and moneylines are on /schedule for Pro keys.

Which plan includes the props API?

Pro, at $29 a month or $249 a year. Free and Basic keys calling /props or /defense get HTTP 403 with reason pro_required; the same key works after upgrading.

How accurate are the prop probabilities?

Each response includes the stat's walk-forward backtest on 2025 and 2026 games: Brier score, log loss, the base-rate Brier score and a calibration table. They are model estimates, not betting advice.

Which stats can I price?

pass_yds, pass_td, pass_att, pass_cmp, pass_int, rush_yds, rush_att, rush_td, rec, rec_yds and rec_td, for QBs, RBs, WRs and TEs, up to 10 lines per request.