The vig is the reason every sportsbook stays profitable long-term. It's a built-in commission baked into the posted odds — and most bettors barely notice it until the losing runs stack up.
What exactly is the vig on a moneyline bet?
Also called juice or overround, the vig is the gap between what you'd be paid at true odds and what the book actually pays. At a standard spread price of -110 on each side, the implied probability for each side works out to roughly 52.4%. Add both sides together: 52.4% + 52.4% = 104.8%. That extra 4.8% is the house's edge, period.
Moneyline markets work the same way. If a favorite is posted at -170 and the underdog at +145, the combined implied probability exceeds 100%. The sportsbook didn't make a mistake — that cushion is intentional.
Why does the vig matter more on moneylines than spreads?
On spreads, -110 is the near-universal price, so the vig is easy to spot. Moneyline odds vary wildly by matchup, which makes the embedded juice harder to eyeball. A -300 favorite and a +240 underdog look straightforward. Run the implied probabilities and the combined total is closer to 106–108%. That extra percentage is pure sportsbook margin.
Over dozens of bets at similar prices, even a 4–5% overround grinds down a bankroll noticeably. Use the moneyline bet calculator to check implied probability on both sides before placing a bet — it takes ten seconds.
How do you reduce the vig's impact?
The most practical answer is line shopping across FanDuel, DraftKings, BetMGM, Caesars, bet365, and BetRivers. Moving a single line from -115 to -110 saves $5 per $100 wagered. That compounds fast. Some books post slightly tighter vig on certain sports or specific markets, so checking multiple sportsbooks before committing is worth the habit.
Understanding the moneyline payout formula also helps — once you can calculate implied probability by hand, inflated lines become obvious immediately. No tool eliminates the vig entirely; it's structural. But knowing it exists — and by how much on any given line — is the first step to making smarter decisions. Must be 21+ (18+ in Wyoming and Tennessee). Gambling problem? Call 1-800-GAMBLER.