What is an Underdog in Sports Betting? What does Underdog Mean?

What is an Underdog?

The underdog is the player or team that the oddsmakers expect to lose. An underdog is a common word in everyday life beyond sports, that is used to describe any person, player, team, idea etc. that is likely to lose, as opposed to the favorite, which is the team expected to win. 

How do I know who the Underdog is?

When the lines are listed on sportsbooks, the underdog will have a plus sign (+) next to its name both on the point spread and the moneyline (in American odds). Occasionally there will be a tight matchup where the favorite might only be -115 on the moneyline and the “underdog” would not have a plus, but only be -105. While certainly not the favorite, a -105 line does not heavily imply that the team is expected to lose and the general public probably wouldn’t use the term underdog.

Underdog Examples:

Let’s take a look at some examples. This screenshot below is the lines for Wild Card Weekend in the NFL.

As mentioned, the teams with the “+” next to the numbers in both the point spread and moneyline category are the underdogs.

The largest underdog (least likely winner) is the Pittsburgh Steelers, who are +12.5 on the point spread and +460 on the moneyline, meaning if a bettor risks $100 on the Steelers to win, the ticket will pay $460 for a total return of $560 including the risk/stake.

In the case of both the point spread and the moneyline, the higher the number after the plus is, the heavier underdog the team is, and the least likely they are to win.

Should I Bet on Underdogs?

Yes, but like all bets, only if the conditions are right. While underdogs lose the game the majority of the time, the high return from an underdog winning payout can mean one win evens out several losses. 

For example, if a bettor placed 100 bets exclusively on -200 moneyline favorites 67 of the bets have to win to make money. Betting on +200 underdogs, only 34 would need to win to turn a profit 

On the point spread, underdogs cover more often than the favorites in the NFL historically, but not enough to profit because of the vig. 

Underdog Betting Strategies:

Do not make any bets blindly, and that goes for blindly taking underdogs just because of the slight higher historical win rate. Instead, use the free odds comparison tools on OddsJam to find the best line for you. Often if one book has an underdog at say +300, another may have +350. Those $50 can make a huge difference on a $100 bet. For subscribers, the +EV betting tool consistently has mathematically profitable underdog wagers on it. If a book’s line is +300 while the OddsJam perfect line is +220? That is a great bet to make, even though it will lose more times than not.

Another strategy is to get in on lines early. This applies to all forms of bets, not just underdogs, but in especially college basketball large spreads can move several points. It’s not uncommon to be able to bet a heavy underdog at say +24.5 on the point spread the night before the game, and by the time the game begins it’s down to +19.5 and you got five points of value which is massive. 

This obviously isn’t happening on every game and line movement isn’t always predictable, but when betting an underdog you want to ensure you have the most points possible to work with at fair odds.

Check out also what does chalk mean in sports betting.