Arbitrage Scanner

When the same event is priced differently on Polymarket and Pinnacle — and the spread holds for days rather than seconds — that's a durable mispricing. The scanner finds them automatically.

→ Live Dashboard

Current opportunities with the 5-dimension traffic light, per-market detail view, pendant quote, spread history. Auto-refresh every 4 hours.

Open Mispricing Lab →

What the scanner does

Polymarket markets with ≥ 14 days remaining and ≥ $50,000 volume are checked against a pendant market. Pinnacle Sportsbook (vig-adjusted via the Power method) is the universal anchor for sport outrights, US politics, geopolitics, and awards. Domain specialists — EODHD ZQ Fed-Funds futures for US rates, Finnhub Economic Calendar for macro releases — cover the non-Pinnacle domains.

Five-dimension traffic light

Instead of a monolithic score, every opportunity is graded along five orthogonal dimensions:

  • Liquidity — 24h volume + open interest on Polymarket. Green ≥ $100k vol + $200k OI.
  • PM spread — bid-ask in cents. Green ≤ 3¢, yellow ≤ 6¢.
  • Match class — A (identical), B (1 deviation), C (multiple). Classifier-confidence downgrade below 0.85.
  • Spread size — abs(pp) between PM and pendant, after costs (slippage + vig + platform fees).
  • Persistence — how long does the spread hold? Green when stable for 7+ days, red on daily-flip patterns.

Aggregate: ≥ 2 reds → red. ≥ 3 greens and no reds → green. Otherwise yellow.

Durable focus

Unlike classical high-frequency arbitrage, this scanner explicitly targets spreads that hold for days to weeks. Preconditions: minimum 14 days remaining, fundamental pendant source rather than cross-platform latency plays. If a mispricing sits in plain sight for two weeks, the thesis is "Polymarket prices this differently than the market does" — not "one API is 80ms faster".

Current coverage

  • Sport outrights — NHL Stanley Cup, NBA Finals, NFL Super Bowl, MLB World Series, NCAA, FIFA World Cup, UEFA Champions League, Bundesliga, Premier League, La Liga, Serie A.
  • US politics — presidential election outrights via the Pinnacle politics sport key.
  • Awards — Oscar Best Picture.
  • Macro — CPI, NFP, Fed decisions via Finnhub consensus.
  • Rates — FOMC hike probabilities derived from EODHD ZQ Fed-Funds futures (CME-FedWatch methodology, computed in-house).

Tech stack

  • Polymarket Gamma API → 4-hour cron filters ~10,000 markets down to ~1,900 durable.
  • Claude Haiku 4.5 classifies into canonical form (event_label, outcome_label, expected_pinnacle_match). 7-day cache, ~$3-5/month at current cadence.
  • Pendant-adapter stack (Pinnacle-first, domain fallback) does the lookup. The Odds API for Pinnacle quotes, vig removed via Power method.
  • Match engine writes opportunity records to KV. Dashboard reads directly — no extra server.