Every sports bettor knows the pain of “The Hook.” You bet the Chiefs -3.5, and they win by exactly 3. You lose. Naturally, the temptation to “buy” that half-point (moving the line from -3.5 to -3.0) is strong.
However, sportsbooks charge a premium for this luxury (usually moving odds from -110 to -125 or -130). Is it worth it? Our Half Point Calculator mathematically compares the Cost of the improved odds against the Value of the number you are crossing. It uses historical data on “Key Numbers” (especially for the NFL) to tell you if you are making a sharp move or falling into a sucker bet.
Half Point Calculator
How to Use the Calculator
This tool performs a Break-Even analysis on your potential bet. Here is how to configure it:
- Select the Sport:
- NFL: Uses a specific probability matrix because scoring is not random (3, 7, and 10 are highly frequent margins).
- NBA/NCAA: Uses a flatter distribution curve, as basketball scoring is more fluid.
- Enter Original Bet:
- Line: The spread currently offered (e.g., -3.5).
- Odds: The price (e.g., -110).
- Enter New Bet (Buying):
- New Line: The line you want to move to (e.g., -3.0).
- New Odds: The price the bookie is charging for that move (e.g., -130).
- The Verdict: The calculator compares the “Implied Probability Cost” vs. the “Push Probability.” If the probability of the game landing on that number is higher than the extra juice you are paying, it is a Good Value bet.
Real-World Examples: The “Key Number” Rule
Buying points is almost exclusively a math problem regarding the numbers 3 and 7 in the NFL.
Example 1: Buying the “3” (Good Value)
The line is -3.5 (-110). You want to buy to -3.0 (-125).
- The Cost: Moving from -110 to -125 increases the break-even percentage by about 3.1%.
- The Value: Historically, about 15% of NFL games end with a margin of exactly 3 points.
- Verdict: You are paying 3.1% to cover an outcome that happens 15% of the time. This is Excellent Value (+EV).
Example 2: Buying the “Dead Numbers” (Bad Value)
The line is -5.5 (-110). You want to buy to -5.0 (-130).
- The Cost: Moving from -110 to -130 costs about 4.3% in implied probability.
- The Value: The margin of 5 is a “dead number” in the NFL. It hits roughly 3.5% of the time.
- Verdict: You are paying 4.3% for protection that only helps you 3.5% of the time. This is Negative Value (-EV). You are better off keeping the -5.5.
Frequently Asked Questions (FAQ)
What are “Key Numbers” in the NFL?
Key numbers are margins of victory that happen most frequently due to the scoring system (Touchdown = 7, Field Goal = 3). The most important numbers are 3 (approx. 15% of games) and 7 (approx. 9% of games). Buying onto or off these numbers is often strategic, whereas buying other numbers is usually a waste of money.
Should I buy points in the NBA?
Generally, no. Unlike the NFL, NBA scoring moves by 1, 2, and 3 points rapidly, creating a much flatter distribution of final margins. It is rarely mathematically profitable to pay the “vig” (juice) to move a basketball spread by half a point.
What does “Buying the Hook” mean?
The “Hook” refers to the half-point (.5) attached to a spread, like -3.5 or +7.5. It guarantees a win or loss (no pushes). “Buying the hook” means paying extra for better odds to turn that half-point into a whole number (e.g., moving -3.5 to -3.0), giving you the safety of a “Push” (tie) if the game lands exactly on the number.