Our cross-venue engine at StartupHub.ai has surfaced four live prediction market arbitrage opportunities as of July 23, 2026. These opportunities involve the same real-world event being priced on two different platforms-Polymarket, Kalshi/Robinhood, and PredictIt-where buying a 'YES' contract on one venue and a 'NO' contract on another totals less than $1. This locks in a guaranteed payout, regardless of the event's outcome.
While spreads can move quickly and opportunities may close fast, four specific arbitrage plays are currently active. Any other spreads that opened in the last few hours may have already closed. It is important to note that fees, KYC requirements, and withdrawal limits can impact actual returns.
Track these live, or poll the free API
The board above refreshes on its own, so this page stays current long after today. The full cross-venue feed lives on the arbitrage board, and every match is also a free JSON API and an MCP tool, so a trading agent can poll live Polymarket, Kalshi and PredictIt arbitrage opportunities and act on them.
curl https://www.startuphub.ai/api/v1/arbitrage?arbs_only=1Read the arbitrage API reference or open the live JSON endpoint.
Informational feed, not financial advice. Live arbitrages are often fleeting, and fees, gas, KYC and withdrawal limits eat into the spread. Verify each market’s resolution rules and costs before trading.