Prop Bet Calculator — Player & Game Props
Calculate payouts for player props, game props, and same-game parlays. See implied probability for any prop line.
What Are Prop Bets?
Proposition bets (props) are bets on specific occurrences within a game rather than the final outcome. Player props: Will Patrick Mahomes throw over/under 275.5 passing yards? Game props: Will there be a score in the first 5 minutes? Same-game parlays (SGPs): Combine multiple props from the same game into a parlay. Props are the fastest-growing segment of sports betting revenue.
Finding Value in Props
Props typically carry higher vig (6-15%) than spreads and totals (4-5%) because sportsbooks spend less time sharpening prop lines. This creates more opportunities for informed bettors. Specialized prop models that incorporate player-specific data (matchup history, snap counts, target share) can find consistent edges. The player prop market is where most new sharp bettors find their first sustainable edge.
DraftKings and FanDuel earn approximately 40% of their handle from same-game parlays and player props — double the margin of spread and total bets. This is why these platforms aggressively promote SGPs: the house edge is 15-25% compared to 4-5% on straight bets.