Point Spread Sports Calculator
See what a spread means as a moneyline and a chance.
How to Use This Calculator
- Type in the point spread (for example -3.5 for a 3.5-point favorite)
- Enter the juice/vig (defaults to -110)
- See the implied win probability and the matching 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's a point spread?
A point spread is a handicap put on the favored team to balance the betting. A team at -3.5 has to win by 4 points or more for the bet to land. The underdog at +3.5 cashes if they win outright or lose by 3 points or fewer.
How do you turn a spread into a moneyline?
Each point of spread works out to roughly 2.75% of win probability. A -3.5 spread points to about a 59.6% win probability, which comes out to around a -148 moneyline for the favorite.
What are juice and vig?
Juice (or vig) is the cut the sportsbook takes. Standard juice is -110 on each side, so you stake $110 to win $100. That built-in margin is what keeps the sportsbook in profit whatever the result.
Is this conversion exact?
The spread-to-moneyline conversion is just an approximation. The precise relationship shifts with the sport, the specific matchup, and market conditions. It’s most useful as a quick guide for NFL and NBA betting.