Point Spread Calc
Turn a spread into a moneyline and a probability.
How to Use This Calculator
- Enter the point spread (e.g., -3.5 for a 3.5-point favorite)
- Enter the juice/vig (default -110)
- Read off the implied win probability and the 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's a point spread?
A point spread is a handicap hung on the favoured team to level the playing field. A team at -3.5 must win by 4 or more for the bet to land. The underdog at +3.5 cashes if they win outright or lose by 3 or fewer.
How do you turn a spread into a moneyline?
Every point of spread maps to roughly 2.75% of win probability. A -3.5 spread implies about 59.6% win probability, which works out to roughly a -148 moneyline for the favorite.
What's juice, or vig?
Juice (or vig) is the cut the sportsbook takes. Standard juice runs -110 a side, meaning you stake $110 to win $100. That built-in margin keeps the sportsbook in profit whatever the result.
Is the conversion exact?
No — the spread-to-moneyline conversion is an approximation. The precise relationship shifts with the sport, the specific matchup, and market conditions. Treat it as a quick reference, best suited to NFL and NBA betting.