What is Key Numbers?

Key numbers are the most frequent margins of victory in a sport, and they carry disproportionate weight in point-spread and totals betting. In American football, the dominant margins are 3 and 7, reflecting the scoring values of the field goal and the touchdown with conversion, followed at lower frequency by 6, 10, 14 and 17. A meaningful share of all games land on exactly these figures. Worked example: roughly 15% of NFL games are decided by exactly 3 points and about 9% by exactly 7. That makes the difference between a spread of -3 and -3.5 far larger than the half-point gap suggests, because moving from -3 to -3.5 means a three-point win, which would have been a push, now becomes a loss. This is why buying the half point from -3.5 to -3 costs a steep premium in extra juice, sometimes -130 or worse, whereas buying from -4.5 to -4 — across a far rarer margin — is cheaper. Why it matters: understanding key numbers is essential for evaluating whether a line is good value, when to buy or sell points, and how to construct teasers. The classic six-point football teaser deliberately moves spreads through both 3 and 7, the two richest numbers, which is what gives the strategy its historical edge. A common mistake is paying full price to buy a half point across a non-key number such as 4 or 11, where the gain in win probability does not justify the added cost. See also buy points, key-numbers-related point spread and teaser.