Using Vegas Lines for NFL DFS: Totals, Spreads and Implied Team Totals

Betting markets are one of the best free sources of information for DFS. Lines are set by bookmakers and adjusted by a market with a lot of money behind it, so they are a sharp, constantly updated estimate of how many points each team is expected to score. You don't need to bet to use them.

The game total

The game total, or over/under, is the market's estimate of the combined points both teams will score. A game with a total of 51 is expected to be much higher scoring than one with a total of 38.

More points means more touchdowns and yards to go around, so high-total games tend to produce the most fantasy points. They are also where most of the field will look first, which is why the highest-total game is usually the most popular game to stack.

The point spread

The spread is the market's estimate of the margin of victory. A team listed at -7 is expected to win by about a touchdown, and its opponent is listed at +7.

The spread hints at game script. Big favorites are expected to lead, and teams with leads tend to run the ball more late in games, which helps their running backs and defense. Big underdogs are expected to trail, and trailing teams tend to throw more, which can help their quarterback and pass catchers even in a loss.

Implied team totals

Combining the total and the spread gives each team's implied total, the number of points the market expects that team to score. Take half the game total, then add half the spread to the favorite and subtract it from the underdog.

For example, in a game with a total of 48 and one team favored by 6, half the total is 24. Half the spread is 3. The favorite's implied total is 27, and the underdog's is 21. Implied team totals are often more useful than the game total, because they show which offense is expected to do the scoring.

Line movement

Lines move during the week as news and betting action come in. A total climbing from 44 to 47 suggests the market now expects more scoring, possibly because of an injury on one defense or improving weather. A total falling sharply can point to weather concerns or a key offensive injury.

Check lines close to lock, not just early in the week. The most recent numbers include the most information.

Player props

Many sportsbooks also post player props: lines for an individual player's passing yards, receptions, rushing yards or chance to score a touchdown. Props are a useful check on your projections. If the market sets a receiver's receiving yards line well above what you project, it's worth asking what you might be missing.

Limits of the market

• Lines are estimates, not outcomes. A 51-point total will sometimes produce a 30-point game.
• Because everyone can see the lines, high-total spots are usually popular. Use the market to find good spots, then use ownership to decide how to play them.
• The market prices the most likely outcome. Tournament success often comes from the less likely outcomes the market expects less often.