parlay-api

Official JavaScript/TypeScript SDK for ParlayAPI: real-time sports odds across 30+ sportsbooks and sources, 90+ sports and leagues, player props, arbitrage and +EV detection, prediction markets (Kalshi, Polymarket), and closing-line history back to 2005.

• Zero runtime dependencies. Native fetch. Works in Node.js 18+ and modern browsers.
• TypeScript types included. Ships ESM and CommonJS builds.
• Drop-in compatible with the-odds-api (toaCompat mode uses the same /v4 paths and response shapes).
• Sandbox mode: explore realistic data with NO API key and no credit cost.
• Mirrors the official Python SDK (pip install parlay-api), same methods, same semantics.

Install

npm install parlay-api

Quickstart (no key needed)

import { ParlayAPI } from "parlay-api";

const client = new ParlayAPI({ sandbox: true });

const sports = await client.sports();
const odds = await client.odds("basketball_nba", {
  regions: "us",
  markets: ["h2h", "spreads", "totals"],
});
console.log(odds[0].bookmakers[0].markets[0].outcomes);

Sandbox mode serves realistic synthetic data from the live API's /v1/sandbox endpoints: perfect for development and CI. When you are ready for live odds, grab a free key (free tier: 1,000 credits/month, no card) and drop the flag:

const client = new ParlayAPI({ apiKey: process.env.PARLAYAPI_KEY });
// or just: new ParlayAPI("YOUR_KEY")

What you can do

// Player props across books (DFS pick'em lines included)
const props = await client.props("baseball_mlb", {
  markets: ["player_strikeouts", "player_total_bases"],
  bookmakers: ["draftkings", "pinnacle", "fanduel"],
});

// Guaranteed-profit arbitrage, 3-way soccer markets included
const arbs = await client.arbitrage("soccer_england_premier_league", {
  minProfit: 1.0,
});

// +EV bets vs a sharp book's no-vig fair line
const evBets = await client.ev("basketball_nba", { minEdge: 2.5 });

// Prediction markets mapped onto the same sport keys
const pm = await client.predictionMarkets("americanfootball_nfl", {
  sources: ["kalshi", "polymarket"],
});

// Historical snapshots and closing lines (game lines from 2005)
const snap = await client.historicalOdds("basketball_nba", "2024-06-01T00:00:00Z");
const closers = await client.closingOdds("baseball_mlb", { season: 2024 });

// Grade one bet: fair price, best book, EV, Kelly, BET/LEAN/FAIR/PASS
const call = await client.verdict({
  sport: "basketball_nba",
  team: "Boston Celtics",
  side: "Boston Celtics",
  market: "h2h",
  bankroll: 1000,
});

// Devig math helpers, no network needed
import { devig, edge, kellyStake } from "parlay-api";
const [fairOver, fairUnder] = devig(-110, -110);

Full method list: sports, odds, events, scores, historicalOdds, closingOdds, props, propMarkets, futures, predictionMarkets, searchPredictionMarkets, arbitrage, ev, consensus, middles, verdict, parlayVerdict, bestBets, setBettableBooks, bettableBooks, usage, websocketUrl, streamOdds, plus the odds-math helpers (americanToImplied, americanToDecimal, decimalToAmerican, impliedToAmerican, devig, edge, kellyStake).

Migrating from the-odds-api

import { OddsAPI } from "parlay-api"; // alias for ParlayAPI

const client = new OddsAPI({ apiKey: KEY, toaCompat: true });
// Same /v4 paths, same response shapes, same x-requests-* quota headers.
const odds = await client.odds("baseball_mlb", { markets: "h2h,spreads,totals" });
console.log(client.lastQuota); // { requestsUsed, requestsRemaining, requestsLast }

Streaming

WebSocket and SSE streaming require Business tier or above (see pricing).

for await (const frame of client.streamOdds("basketball_nba")) {
  console.log(frame); // full snapshot on connect, then pushed updates
}

streamOdds uses the runtime's global WebSocket (browsers, Node 22+). On older Node, pass an implementation via options.webSocket or build the URL yourself with client.websocketUrl(sportKey).

Errors and quota

Typed errors mirror the Python SDK: InvalidAPIKeyError (401), CreditLimitExceededError and TierGatedError (403), RateLimitedError (429), ParlayAPIError for everything else. Every successful call refreshes client.lastQuota from the x-requests-* response headers.

The data behind it

Verified against the live API and production database, as of 2026-08:

• 90+ sports and leagues (GET /v1/sports lists all of them)
• 30+ sportsbooks and sources, sub-5-second freshness on major books
• 4,000+ distinct player-prop markets
• 1.7M+ historical game closing lines, continuous from 2005
• 30M+ prop closing lines archived since 2022
• 200 API endpoints (openapi.json)
• Free tier: 1,000 credits/month, no card required; paid tiers at parlay-api.com/pricing

Prefer an agent to write this code for you? ParlayAPI also ships a 22-tool MCP server: pip install parlayapi-mcp.

Examples

The examples/ folder has runnable scripts (sandbox by default, no key needed):

node examples/quickstart.mjs
node examples/arb_finder.mjs
node examples/ev_scanner.mjs

Development

npm install     # dev dependency: typescript only
npm run build   # emits dist/esm, dist/cjs, dist/types
npm test        # smoke test against the live sandbox endpoints

License

MIT