Point Spread Calculator

Convert point spreads to moneylines and implied probabilities. See what a spread means in terms of win probability and equivalent moneyline odds.

Please enter a valid spread
Results
Favorite Win Probability --
Favorite Moneyline --
Underdog Win Probability --
Underdog Moneyline --
Juice Implied Probability --

How to Use This Calculator

  1. Enter the point spread (e.g., -3.5 for a 3.5-point favorite)
  2. Enter the juice/vig (default -110)
  3. View the implied win probability and equivalent moneyline for both sides

Formula

Implied Probability from Juice:

  • For negative odds: Probability = |Odds| / (|Odds| + 100)
  • For positive odds: Probability = 100 / (Odds + 100)

Spread to Moneyline (approximation):

  • Each point of spread ≈ 2.75% shift from 50/50

Probability to American Moneyline:

  • If prob ≥ 50%: Moneyline = -100 × prob / (1 - prob)
  • If prob < 50%: Moneyline = +100 × (1 - prob) / prob

Frequently Asked Questions

What is a point spread?

A point spread is a handicap applied to the favored team to even out the betting. If a team is -3.5, they must win by 4 or more points for the bet to win. The underdog at +3.5 wins if they win outright or lose by 3 or fewer points.

How do you convert a spread to a moneyline?

Each point of spread roughly corresponds to 2.75% of win probability. A -3.5 spread implies approximately 59.6% win probability, which converts to roughly a -148 moneyline for the favorite.

What is juice or vig?

Juice (or vig) is the commission the sportsbook charges. Standard juice is -110 on each side, meaning you must bet $110 to win $100. This built-in margin ensures the sportsbook profits regardless of the outcome.

Is this conversion exact?

The spread-to-moneyline conversion is an approximation. The exact relationship depends on the sport, the specific matchup, and market conditions. It works best as a quick reference for NFL and NBA betting.