Are Overs or Unders Better?
The real return of blindly betting overs vs unders on player props, settled at the closing line across more than 1 million graded props. Unders lose less in every sport, because the public bets overs and books shade the over price.
Blind ROI by sport
Return on betting every over vs every under, 1 unit flat, settled at the closing line. The gap between the bars is the over/under bias.
MLB over time
Cumulative blind ROI; where it settles is the long-run edge. Gray bars are bets settled each month.
Props included
What went into MLB and how each prop settled, on the closing line. Win/Loss/Push are the over side (a loss is an under win); void = no action, pending = not yet graded.
| Prop | Bets | Win | Loss | Push | Void | Pending | Over ROI | Under ROI |
|---|---|---|---|---|---|---|---|---|
| Total Bases | 394,207 | 187,833 | 206,374 | 0 | 56,832 | 4,045 | -8.5% | -5.7% |
| Hits | 239,471 | 135,450 | 104,021 | 0 | 36,827 | 3,185 | -6.7% | -7.8% |
| Stolen Bases | 97,947 | 8,692 | 89,255 | 0 | 12,032 | 674 | -40.5% | -2.4% |
| Home Runs | 55,704 | 8,018 | 47,686 | 0 | 6,075 | 693 | -22.9% | -4.5% |
| Pitcher Strikeouts | 43,798 | 21,244 | 22,170 | 384 | 2,668 | 1,081 | -7.6% | -6.0% |
| Runs + RBIs | 42,399 | 20,297 | 22,102 | 0 | 7,704 | 5 | -6.0% | -6.3% |
| Earned Runs Allowed | 30,439 | 14,256 | 16,183 | 0 | 2,071 | 282 | -11.4% | -2.8% |
| Pitching Outs | 29,808 | 15,227 | 14,525 | 56 | 1,502 | 608 | -5.7% | -9.2% |
| Hits Allowed | 27,218 | 13,267 | 13,862 | 89 | 927 | 343 | -8.6% | -5.7% |
| Singles | 18,682 | 8,399 | 10,283 | 0 | 2,750 | 0 | -11.7% | -9.6% |
| RBIs | 18,648 | 5,538 | 13,110 | 0 | 2,663 | 0 | -17.6% | -7.0% |
| Runs | 18,590 | 7,085 | 11,505 | 0 | 3,340 | 26 | -15.9% | -7.4% |
| Walks Earned | 17,352 | 5,553 | 11,799 | 0 | 1,709 | 0 | -17.0% | -7.6% |
| Doubles | 14,516 | 2,325 | 12,191 | 0 | 1,626 | 0 | -28.6% | -4.2% |
| Pitcher Base On Balls | 1,675 | 865 | 810 | 0 | 42 | 0 | -7.8% | -13.1% |
| Hitter Strikeouts | 479 | 228 | 251 | 0 | 27 | 0 | -14.4% | -6.4% |
| Walks Allowed | 230 | 113 | 117 | 0 | 7 | 0 | -14.9% | -9.6% |
Over vs under ROI by sport
Blindly betting every over vs every under, 1 unit flat, settled at the closing line across all books. A negative number loses to the vig; the gap between the columns is the over/under bias.
| Sport | Graded props | Over ROI | Under ROI |
|---|---|---|---|
| MLB | 1,051,163 | -12.5% | -6.0% |
| NBA | 375,339 | -8.7% | -3.8% |
| NHL | 158,686 | -9.5% | -4.7% |
| WNBA | 119,377 | -8.7% | -5.2% |
| NFL | 43,194 | -10.5% | -1.5% |
| CFB | 29,025 | -10.5% | -2.3% |
| CBB | 8,157 | -15.4% | +3.3% |
Drill into the lopsided markets
Sport-level is the headline. The edge is in the detail: which books shade hardest, which prop types are most one-sided, and which players the lines consistently misprice. Subscribers get the full breakdown by book, prop, and player, plus saved reports.
See plans →How this connects to devig
The standard way to remove the vig from a line (the multiplicative method) silently assumes the book split its juice evenly between the two sides. This page is the proof that it doesn't. When overs are shaded, a plain devig hands you a fair line that's still tilted. Our devig calculator factors the measured bias back in.