For newcomers, a prediction market arbitrage lock occurs when buying a 'YES' contract on one venue and a 'NO' contract for the same real-world event on another venue costs less than $1 combined, guaranteeing a profit regardless of the outcome.
StartupHub.ai's proprietary cross-venue engine has surfaced 10 such live opportunities as of August 9, 2026. These spreads, spanning Polymarket, Kalshi/Robinhood, and PredictIt, offer varying returns by exploiting temporary pricing inefficiencies.
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.
Focused guides: Polymarket arbitrage, Kalshi arbitrage, and the arbitrage bot API.
