PropLine API Review 2026

PropLine is a sports odds API built around player props. Most odds APIs treat props as a secondary market bolted onto game lines. PropLine inverts that: 60+ prop market types are first-class, with game lines (moneylines, spreads, totals) available alongside them. The API covers 54 sports across 15 sportsbooks and 5 exchanges, including Pinnacle, DraftKings, FanDuel, Bovada, and prediction markets like Kalshi and Polymarket.

The pitch goes beyond raw odds. PropLine resolves props against actual box scores and tells you whether a line hit, lost, or pushed. It calculates no-vig fair lines and flags cross-book +EV opportunities. It tracks line movement and runs steam detection. If your work starts with "which props have value right now," PropLine tries to answer that question inside the API itself rather than leaving the math to you.

PropLine lists 54 sports, though the practical depth varies. US majors (MLB, NFL, NBA, NHL, WNBA, NCAAF) get the deepest prop coverage. Soccer spans 28 leagues. UFC, boxing, tennis, and golf round out the list.

The 60+ prop market types are the differentiator. Baseball alone covers strikeouts, earned runs, hits, stolen bases, and batting stats. Basketball includes points, rebounds, assists, three-pointers, and double-doubles. Hockey has goals, shots, saves, and blocked shots. Period-specific markets (Q1, H1, P1, first-5-innings) are available through a query parameter rather than separate endpoints.

Book coverage is narrower than the big aggregators. You get 15 sportsbooks and 5 exchanges, not 300. The set tilts toward US-facing books and DFS platforms (PrizePicks, Underdog Fantasy, Sleeper). If you need a wide international book selection, this is not the right fit. If you need deep US props from the books that actually post them, the coverage matches the use case.

One useful detail: the response format is drop-in compatible with The Odds API's schema. If you already parse that format, switching costs are low.

Three features separate PropLine from a generic odds feed:

• Closing lines. The /closing endpoint returns opening and closing prices for resolved events, so you can calculate closing line value (CLV) without storing the feed yourself. Available from the Hobby tier ($9/mo) onward.
• +EV scoring. The /ev endpoint compares each book's price against a no-vig fair line anchored to Pinnacle or Bovada and flags positive expected value. Useful if you want the math done server-side.
• Steam detection. The /movement endpoint scores line moves on a 0 to 100 scale based on multi-book consensus. A high score means several books moved the same direction in a short window.

These are analytical features, not raw data. If you prefer to run your own models and only want clean odds, you can ignore them and use PropLine as a straight props feed. But they are the reason to pick this API over a broader aggregator that covers more books with less analysis. For more on how closing lines fit into a betting workflow, see the historical odds guide.

Pricing is published and starts at zero:

• Free: 1,000 requests/day. Game lines, scores, futures, stats, and context. No props history, no +EV, no closing lines.
• Hobby, $9/mo: 5,000 requests/day. Adds prop resolution, +EV scoring, line movement, closing lines, and 30-day history.
• Pro, $19/mo: 25,000 requests/day. Adds 90-day archive and CSV exports.
• Streaming Lite, $39/mo: 100,000 requests/day. Adds webhooks (HMAC-signed, with retry logic) and 180-day history.
• Streaming, $79/mo: 1,000,000 requests/day. Up to 10 webhooks and 365-day history.
• Enterprise: custom pricing for unlimited access.

Annual billing saves two months. A one-time $99 backfill option adds 7 days of historical tick data to any tier.

The free tier is genuinely usable for prototyping. It covers game lines, stats, and event context at 1,000 requests per day, which is enough to build a working integration and see the response shape. The analytical features (the reason you would pick PropLine specifically) start at $9/mo on Hobby, which is a low threshold to test whether the +EV and closing-line endpoints add value to your workflow.

The API lives at https://api.prop-line.com/v1. Authentication works through either a query parameter (?apiKey=) or a header (X-API-Key). Every response includes quota headers (X-Daily-Limit, X-Daily-Used, X-Daily-Remaining) so you can pace yourself without guessing.

Real-time delivery uses webhooks rather than a persistent WebSocket connection. You register a callback URL with event filters (line movement, resolution, steam) and PropLine pushes HMAC-signed payloads to it. The retry policy escalates from 10 seconds to 1 hour across 6 attempts. Webhooks require the Streaming Lite tier or above.

Polling cadence on REST is 60 seconds for pre-game data and 30 seconds during live games. That is fine for props analysis but too slow for latency-sensitive arbitrage on game lines.

SDKs exist for Python (pip install propline) and Node.js (npm install propline), plus a CLI tool and an MCP server (npx -y propline-mcp) for Claude Desktop and Claude Code integration. The MCP server is an official release from PropLine.

The product is built for a specific slice of the market:

• Props modelers who build projections and need cross-book prop prices with resolution data to grade their accuracy.
• +EV bettors who want server-side edge detection rather than building the no-vig math themselves.
• DFS players who need PrizePicks and Underdog pricing alongside sportsbook props, with payout multipliers and breakeven rates included.
• CLV trackers who measure their betting performance against closing lines and want that data from the API directly.

Skip it if you need broad international bookmaker coverage. Fifteen US-facing books is a narrow set compared to aggregators that cover hundreds. Skip it too if your primary need is game-line arbitrage at low latency, since the 30-to-60-second polling cadence is not fast enough. For those use cases, browse the sports odds API directory for wider options.

PropLine is a props-first API that does more analysis than most odds feeds. Closing lines, +EV flags, steam detection, and graded results are built into the endpoints rather than left as an exercise for the developer. The pricing is low enough to test the analytical features before you commit.

The tradeoffs follow directly from the focus. Book coverage is narrow. Polling is not fast enough for real-time arbitrage. The historical archive only goes back to April 2026, so long backtests are not possible yet. If props are your primary market and the analytical layer saves you building it yourself, PropLine is a focused tool that does its job. If you need breadth first and props second, start with a general aggregator and come back here when the props gap bothers you.