What Does -110 Mean?

What does -110 mean in sports betting?

-110 is the most common price you’ll see on point spreads and totals (and often on 50/50 style props). It’s a form of American odds that tells you two things at once:

• Payout rule: how much you win if you’re right.
• Break-even rule: how often you must win to not lose money long term.

Payout and profit

American odds use “win $100 profit” as the reference point for negative odds.

Profit examples at -110

• Stake $100 → profit if win ≈ $90.91 → total return ≈ $190.91
• Stake $110 → profit if win = $100 → total return = $210
• Stake $50 → profit if win ≈ $45.45 → total return ≈ $95.45

General payout formula (negative odds)

For any negative odds -A (where A is positive):

• Profit if you win: profit = stake × (100 / A)
• Total return: stake + profit

Break-even percentage at -110

The implied probability is the break-even win rate for a price. For -110:

• break-even = 110 / (110 + 100) = 0.523809…
• Break-even ≈ 52.38%

Why 52.38% matters

• If you win 50% at -110, you will lose money long term.
• If you win 52.38%, you break even (before any additional costs).
• If you win 55%, you have a meaningful edge.

How -110 “explains” other odds

Once you understand -110, you can understand any American odds because the logic stays the same:

• Negative odds (like -110, -150, -200) mean you must risk more than you win (favorite or expensive price).
• Positive odds (like +120, +150) mean you win more than you risk (underdog or cheaper price).

Implied probability formulas (American odds)

• Positive odds (+A): implied = 100 / (A + 100)
• Negative odds (-A): implied = A / (A + 100)

Vig and why both sides are often -110

A sportsbook bakes in a margin called vig (or juice). That’s why spreads and totals are commonly priced like:

• Side A -110
• Side B -110

Each side implies 52.38%. Added together that’s 104.76%, not 100%. The extra 4.76% is the market’s embedded margin (simplified).

Line shopping (small edges add up)

Small price differences change break-even over volume.

• -105 break-even: 105/205 ≈ 51.22%
• -110 break-even: 52.38%
• -115 break-even: 115/215 ≈ 53.49%

EV connection

Expected value (EV) for a single bet is:

• EV = p(win) × profit − (1 − p(win)) × stake

At -110 with a $100 stake, profit if win is ~$90.91. If you believe the bet wins 55% of the time:

• EV = 0.55 × 90.91 − 0.45 × 100 ≈ +$5.00

Common misconceptions

• “-110 means the bet is 52.38% likely to win.” No. 52.38% is the break-even rate at that price, and it includes the book’s margin.
• “If I’m around 50/50 I’m fine.” Not at -110. 50% at -110 is a losing strategy long term.
• “Only big edges matter.” Small edges matter if you can repeat them consistently and manage variance (bankroll).

Practical checklist

1. Convert the price to break-even (implied probability).
2. Shop for a better number (even 5–10 cents matters).
3. Only use EV when you have a reason for your win % estimate.
4. Expect variance: even +EV betting has losing stretches.