Spread to Moneyline
A spread and a moneyline are two ways of quoting the same game. This turns one into the other, and shows the win probability sitting underneath both.
A 5-point NFL favorite has won about 65.50% of the time. Blended with what these two prices imply, that puts the side at 60.85% — a no-vig moneyline of -155, against +155 on the dog. A posted moneyline worse than that is the book's fee showing.
The moneyline is the same opinion without the points, so it's the safer way to back a side I already like.
The game
NCAAF reads off the NFL table. NBA has its own.
What the spread is worth
These are no-vig numbers. A sportsbook posting the same side will quote it worse, and the difference between the two is what it charges to take the bet.
How often each side wins
Where that number came from
Anything the two prices add above 100% is the fee, not probability. Stripping it out gives each side's share, and the headline blends that share (30%) with the historical win rate for a spread this size (70%). Spreads between table values are interpolated linearly.
Football scores do not land smoothly. Three and seven are where games actually finish, so the step from 2.5 to 3.5 is worth far more than the single point between them suggests, and a table that interpolates straight across that gap will understate it. Basketball margins are smoother, but the deeper limit applies to both: a historical win rate for a five-point favorite is an average across many seasons and many teams, not a read on tonight's matchup. Treat the output as the market's own arithmetic made visible, then check it against the moneyline the book is actually posting.