Today, July 12, 2026, StartupHub.ai's cross-venue engine identified five prediction market arbitrage opportunities across Polymarket, Kalshi/Robinhood, and PredictIt. An arbitrage lock occurs when buying a 'YES' contract on one venue and a 'NO' contract on another for the same real-world event totals less than $1, guaranteeing a profit regardless of the outcome.
Four of these spreads are live right now, offering immediate opportunities for those quick enough to act. One additional opportunity was seen earlier and may have already closed, as spreads on these volatile markets can move very quickly. Please remember, this is not financial advice. Transaction fees, KYC processes, 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.