-397 Odds Explained
- Decimal
- 1.25
- American
- -397
- Fractional
- 25/99
- Implied probability
- 79.88%
- Polymarket
- 80¢
- $100 wins
- 25.19
- The fraction shown is the closest simple fraction to the odds rounded to 3 decimals, not an exact match.
- American
- -397
- Fractional
- 25/99
- Implied probability
- 79.88%
- Polymarket
- 80¢
- Profit
- 25.19
- Total return
- 125.19
1.252 decimal, -397 American, 79.88% implied probability
The price -397 converts to 1.25 decimal odds and 25/99 fractional odds. Read as a probability it says the bookmaker prices this outcome at 79.88%, 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 80¢.
What -397 pays
A 100 stake at -397 returns 125.19 in total: your 100 back plus 25.19 profit. To win exactly 100 you would stake 397.00. The table covers the stakes people actually use.
| Stake | Profit | Total return |
|---|---|---|
| 10 | 2.52 | 12.52 |
| 25 | 6.30 | 31.30 |
| 50 | 12.59 | 62.59 |
| 100 | 25.19 | 125.19 |
| 500 | 125.94 | 625.94 |
| 1,000 | 251.89 | 1,251.89 |
Break-even and long-run results
The implied probability of -397 is 79.88%, and that number is also the break-even win rate: win more often than 79.88% 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% | -37.4% |
| 55% | -31.1% |
| 60% | -24.9% |
| 65% | -18.6% |
| 80% | 0.2% |
At 79.88% 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 79.88% of these bets just to stand still, and one loss wipes out several wins.
The vig at -397
If both sides of a two-way market were priced at -397, the implied probabilities would add up to 59.76% above 100%. That excess is the overround, or vig; as a share of stakes it is a 37.41% 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.
-397 on a betting exchange
Exchanges charge commission on net winnings, so the price you see is not the price you get. At 2% commission -397 is worth 1.247 decimal (-405 American); at 5% it drops to 1.239 (-418). Those are the bookmaker prices you would need to beat.
| Commission | Effective decimal | Effective American | Break-even |
|---|---|---|---|
| 2% | 1.247 | -405 | 80.20% |
| 5% | 1.239 | -418 | 80.69% |
Same price in other formats
Nearby prices
Nearby prices
Frequently asked questions
What does -397 mean in betting?
-397 is an American price. Positive numbers show the profit on a 100 stake; negative numbers show the stake needed to win 100. At -397 the implied probability is 79.88% and a 100 stake returns 125.19.
What is -397 in decimal odds?
-397 converts to 1.252 in decimal odds (usually shown as 1.25). Decimal odds are the total return per unit staked, so multiply your stake by 1.252 to get the return.
What is -397 as a fraction?
-397 is 25/99 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 -397?
A 100 stake at -397 wins 25.19 in profit and returns 125.19 including the stake. To win exactly 100 you would stake 397.00.
What win rate do I need at -397?
The break-even win rate equals the implied probability, 79.88%. Winning more often than that at this price is profitable over the long run; winning less often loses money.