{"uid":"cap_ua_b9XC-haVbgTQyEF081","slug":"kalshi-vs-polymarket-sports-odds-cross-venue-api-0a5bdb0f","name":"Kalshi vs Polymarket Sports Odds Cross-Venue API","description":"Exact EVM address, calldata, Uniswap V2/V3 and impermanent-loss math. Pay per call in USDC on Base via x402.","url":"https://golf-evm-math.x402-evm-math.workers.dev/data/sports-xvenue?utm_source=zero.xyz","method":"GET","headers":{},"bodySchema":{"type":"object","$schema":"https://json-schema.org/draft/2020-12/schema","required":["input"],"properties":{"input":{"type":"object","required":["type","method"],"properties":{"type":{"type":"string","const":"http"},"method":{"enum":["GET"],"type":"string"},"queryParams":{"type":"object","properties":{}}},"additionalProperties":false},"output":{"type":"object","required":["type"],"properties":{"type":{"type":"string"},"example":{"type":"object"}}}}},"responseSchema":{"type":"json","example":{"games":[{"league":"nfl","pm_bid":0.57,"team_a":"SF","team_b":"ATL","best_combo":"pm_long_SF+kalshi_no","all_in_cost":1.0319,"kalshi_yes_ask":0.58,"edge_after_fees":-0.0319}],"age_seconds":120}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.005","displayCostAsset":"USDC","priceDynamic":false,"priceHint":null,"priceStatus":"priced","priceSource":"probe","requiresHandshake":false,"reviewCount":0,"rating":{"score":"0.00","successRate":"0.00","reviews":0,"stars":null,"state":"unrated"},"availabilityStatus":"unknown","priceObserved":null,"sessionDeposit":null,"pricing":{"kind":"static","summary":"$0.005/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.005","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.005","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_GsVuc0eBeSazqywj5AVTJ","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.005","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Returns cross-venue US sports game-winner odds from Kalshi and Polymarket with taker fees and edge-after-fees calculations, updated every 5 minutes.","exampleAgentPrompt":"Pull the latest cross-venue odds for US sports games comparing Kalshi and Polymarket prices, and show me which matchups have the best edge after taker fees right now.","exampleUseCases":[{"title":"NFL arbitrage opportunity scanner","prompt":"Check the current Kalshi vs Polymarket odds for NFL games and tell me which game has the best positive edge after fees — I want to know the best combo strategy and the all-in cost."},{"title":"Pre-game prediction market price check","prompt":"What are Kalshi and Polymarket currently pricing the SF vs ATL game at, and what's my net edge if I take the best available combination across both venues after fees?"},{"title":"Automated odds monitoring bot","prompt":"Every 5 minutes, fetch the latest cross-venue sports odds comparing Kalshi and Polymarket and alert me whenever any game shows a positive edge after taker fees."}],"resultDescription":"A JSON object containing a list of games, each with league, team matchup, Polymarket bid price, Kalshi yes ask price, the best cross-venue combo strategy, total all-in cost, and edge after fees. Also includes data age in seconds to indicate how fresh the feed is.","failureModes":["Stale data if upstream Kalshi or Polymarket APIs are delayed beyond 5-minute refresh window","Empty games array if no active markets are currently listed","Payment failure if USDC micropayment via x402 is not properly configured","HTTP 402 if payment header is missing or insufficient","Negative edge on all games meaning no arbitrage opportunity currently exists"],"whenToPreferThis":"Choose this endpoint when you need a single aggregated view of game-winner prices across both Kalshi and Polymarket with fees already factored in, rather than querying each venue separately and manually computing net edge. Ideal for arbitrage bots, trading agents, or anyone comparing prediction market odds in real time without building their own cross-venue fee model.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-28T06:42:08.905Z","isFirstParty":false,"canonicalSlug":"kalshi-vs-polymarket-sports-odds-cross-venue-api-0a5bdb0f"}