Buy Points Calculator

Buying points lets you move the point spread in your favor in exchange for worse odds (more juice). A standard buy costs 10 cents per half-point: if the line is -3 (-110), buying a half-point to -2.5 moves the odds to -120. Buying a full point to -2 moves them to -130. The sportsbook charges you for each half-point increment. The key question is whether the improved spread, and the resulting increase in your win probability, is worth the extra juice you pay. This calculator answers that question mathematically using margin frequency data.

NFL games disproportionately land on specific margins due to scoring structure. 3 is the most common margin at 15.0% of all games (field goal difference). 7 comes next at 9.1% (touchdown). Then 6 (6.1%), 10 (5.6%), and 14 (4.8%). When you buy through one of these key numbers, you capture a large chunk of outcomes that would otherwise be losses or pushes. This is why buying through 3 is almost always profitable: you're picking up nearly 15% of all game outcomes. Sportsbooks know this, which is why some charge 15-20 cents (instead of 10) to buy through 3.

A buy is +EV when the win percentage gained from the extra points exceeds the break-even cost of the worse odds. The formula: calculate the break-even win % at the original odds (e.g., 52.38% at -110), then at the new odds (e.g., 54.55% at -120). The cost is the difference: 2.17%. Now estimate how much win % you gain from the half-point. If the spread moves from -3 to -2.5, you capture games decided by exactly 3 (where you'd push on -3 but win on -2.5). That's ~15.0% / 2 = ~7.5% win % improvement. Since 7.5% > 2.17%, buying through 3 is clearly +EV. Apply the same logic to any number. Most non-key numbers yield only 2-4% improvement, rarely enough to justify the juice.

A "hook" is the half-point that turns a push into a win or a loss into a push. For example, -2.5 is "off the hook" at 3: if the game lands on exactly 3, you lose. But -3 pushes, and -3.5 wins. Buying from -3.5 to -3 eliminates losses on margins of exactly 3 (converting them to pushes). Buying from -3 to -2.5 converts pushes on 3 into wins. Both have value, but the push-to-win conversion is typically more valuable because a push returns your stake while a win returns profit. The hook matters most around key numbers: buying from -7.5 to -7 or -3.5 to -3 has significantly different value than buying from -5.5 to -5.