Prediction Markets
A prediction market — Kalshi, Polymarket, Novig or ProphetX — is an exchange where traders buy and sell yes/no contracts on an outcome, so the contract's own price is the market's probability estimate, unlike a sportsbook's price, which has a margin built in.
Worked example
A Kalshi contract trading at 42¢ for "yes" is pricing that outcome at roughly a 42% probability, with the venue's own trading fee charged separately on top — a sportsbook, by contrast, bakes its margin into the price itself.
Right now on BeatVig
Across the 497 player props BeatVig prices at both a prediction market and a sportsbook right now, a prediction market is the better price 34% of the time (172 of 497).
In short
A prediction market — Kalshi, Polymarket, Novig or ProphetX — is an exchange where traders buy and sell yes/no contracts on an outcome, so the contract's own price is the market's probability estimate, unlike a sportsbook's price, which has a margin built in. A Kalshi contract trading at 42¢ for "yes" is pricing that outcome at roughly a 42% probability, with the venue's own trading fee charged separately on top — a sportsbook, by contrast, bakes its margin into the price itself.
Prediction Markets — FAQ
What is a prediction market?
A prediction market is an exchange — Kalshi, Polymarket, Novig or ProphetX — where traders set an outcome's price by buying and selling contracts against each other, so the price itself is the market's probability estimate.
Is a prediction market the same as a sportsbook?
No. A sportsbook sets its own price with a margin built in; a prediction market's price is set by traders on both sides, and the venue charges a separate fee rather than folding one into the quote.
Are prediction markets always cheaper than sportsbooks?
No — it depends on the market type and the specific bet. See BeatVig's own live comparison for how often a prediction market is actually the better price right now.
Which prediction markets does BeatVig compare?
Kalshi, Polymarket, Novig and ProphetX, compared against sportsbooks on the same NFL, NBA and MLB games and player props.