-645 Odds Explained
- Decimal
- 1.16
- American
- -645
- Fractional
- 11/71
- Implied probability
- 86.58%
- Polymarket
- 87¢
- $100 wins
- 15.50
- The fraction shown is the closest simple fraction to the odds rounded to 3 decimals, not an exact match.
- American
- -645
- Fractional
- 11/71
- Implied probability
- 86.58%
- Polymarket
- 87¢
- Profit
- 15.50
- Total return
- 115.50
1.155 decimal, -645 American, 86.58% implied probability
The price -645 converts to 1.16 decimal odds and 11/71 fractional odds. Read as a probability it says the bookmaker prices this outcome at 86.58%, which is the share of the time you would need to win just to break even. A prediction market would quote the same chance as 87¢.
What -645 pays
A 100 stake at -645 returns 115.50 in total: your 100 back plus 15.50 profit. To win exactly 100 you would stake 645.00. The table covers the stakes people actually use.
| Stake | Profit | Total return |
|---|---|---|
| 10 | 1.55 | 11.55 |
| 25 | 3.88 | 28.88 |
| 50 | 7.75 | 57.75 |
| 100 | 15.50 | 115.50 |
| 500 | 77.52 | 577.52 |
| 1,000 | 155.04 | 1,155.04 |
Break-even and long-run results
The implied probability of -645 is 86.58%, and that number is also the break-even win rate: win more often than 86.58% of the time at this price and you profit in the long run, win less often and you lose. The table shows the return on stake at a few win rates, including the break-even rate itself.
| Win rate | Return on stake |
|---|---|
| 50% | -42.2% |
| 55% | -36.5% |
| 60% | -30.7% |
| 65% | -24.9% |
| 87% | 0.5% |
At 86.58% this is a heavy favourite. Prices this short appear when one side is expected to win comfortably: a top seed against a qualifier, a strong home team against a relegation candidate, or a moneyline in a game with a double-digit spread. The catch is the payout. You need to win more than 86.58% of these bets just to stand still, and one loss wipes out several wins.
The vig at -645
If both sides of a two-way market were priced at -645, the implied probabilities would add up to 73.15% above 100%. That excess is the overround, or vig; as a share of stakes it is a 42.25% margin for the bookmaker. Removing it leaves fair odds of 2.00 decimal ( +100) on each side. Use the devig calculator to do the same for any market.
-645 on a betting exchange
Exchanges charge commission on net winnings, so the price you see is not the price you get. At 2% commission -645 is worth 1.152 decimal (-658 American); at 5% it drops to 1.147 (-679). Those are the bookmaker prices you would need to beat.
| Commission | Effective decimal | Effective American | Break-even |
|---|---|---|---|
| 2% | 1.152 | -658 | 86.81% |
| 5% | 1.147 | -679 | 87.16% |
Same price in other formats
Nearby prices
Nearby prices
Frequently asked questions
What does -645 mean in betting?
-645 is an American price. Positive numbers show the profit on a 100 stake; negative numbers show the stake needed to win 100. At -645 the implied probability is 86.58% and a 100 stake returns 115.50.
What is -645 in decimal odds?
-645 converts to 1.155 in decimal odds (usually shown as 1.16). Decimal odds are the total return per unit staked, so multiply your stake by 1.155 to get the return.
What is -645 as a fraction?
-645 is 11/71 in fractional odds, the traditional bookmaker notation where the top number is profit and the bottom number is stake.
How much do I win on a 100 bet at -645?
A 100 stake at -645 wins 15.50 in profit and returns 115.50 including the stake. To win exactly 100 you would stake 645.00.
What win rate do I need at -645?
The break-even win rate equals the implied probability, 86.58%. Winning more often than that at this price is profitable over the long run; winning less often loses money.