Prior to the 2019-20 NFL Season, I wanted to expand my Implied Probability calculator. My calculator did simple calculations and conversions to allow me to see which moneyline odds were a good value based on my implied probability. Overall, I had nothing unusual that the average sports bettor would have in their tool belt.
One of the things I wanted to add was a Moneyline to Spread converter.
The problem with this concept is that every sportsbook has different nuances in their booking. With each book having different hold/juice percentages, having a foolproof system is near impossible without tremendous amounts of data–which is expensive.
So what I did was take available data and use the average to create a general overview. As I create and develop my own probabilities based on my algorithms and systems, I can easily calculate an exected spread.
The longevity of a sports bettor relies on a couple of cornerstone principles–getting the best number–is one of them. It’s not unusual for a sportsbook to offer better value on the Moneyline versus the Spread. Use this data to ensure you’re receiving the best value possible.
NFL Moneyline to Spread Conversion
The following data uses NFL averages from the 2018-19 season. This data includes uses the average moneyline and spread from every NFL game last season. The implied probability was then calculated from those averages.
| NFL Spread | Favorite Implied Probability | Favorite Moneyline | Underdog Implied Probability | Underdog Moneyline |
|---|---|---|---|---|
| -1 | 53.70% | -116 | 48.54% | +106 |
| -1.5 | 55.56% | -125 | 48.31% | +107 |
| -2 | 56.14% | -128 | 47.62% | +110 |
| -2.5 | 57.98% | -138 | 45.66% | +119 |
| -3 | 61.54% | -160 | 41.67% | +140 |
| -3.5 | 64.79% | -184 | 38.46% | +160 |
| -4 | 67.53% | -208 | 36.10% | +177 |
| -4.5 | 68.45% | -217 | 35.34% | +183 |
| -5 | 69.79% | -231 | 33.78% | +196 |
| -5.5 | 70.85% | -243 | 32.79% | +205 |
| -6 | 71.59% | -252 | 31.75% | +215 |
| -6.5 | 73.75% | -281 | 29.67% | +237 |
| -7 | 76.25% | -321 | 27.32% | +266 |
| -7.5 | 77.88% | -352 | 25.58% | +291 |
| -8 | 80.24% | -406 | 23.26% | +330 |
| -8.5 | 80.31% | -408 | 23.26% | +330 |
| -9 | 81.41% | -438 | 22.08% | +353 |
| -9.5 | 81.48% | -440 | 22.08% | +353 |
| -10 | 83.25% | -497 | 20.16% | +396 |
| -10.5 | 83.95% | -523 | 19.46% | +414 |
| -11 | 85.42% | -586 | 17.99% | +456 |
| -11.5 | 86.05% | -617 | 17.33% | +477 |
| -12.5 | 87.01% | -670 | 16.42% | +509 |
| -13.5 | 88.58% | -776 | 14.90% | +571 |
| -13 | 88.64% | -780 | 14.81% | +575 |
| -14.5 | 89.05% | -813 | 14.18% | +605 |
| -14 | 91.26% | -1044 | 12.09% | +727 |
