-497 Odds Explained
- Decimal
- 1.20
- American
- -497
- Fractional
- 20/99
- Implied probability
- 83.25%
- Polymarket
- 83¢
- $100 wins
- 20.12
- The fraction shown is the closest simple fraction to the odds rounded to 3 decimals, not an exact match.
- American
- -497
- Fractional
- 20/99
- Implied probability
- 83.25%
- Polymarket
- 83¢
- Profit
- 20.12
- Total return
- 120.12
1.201 decimal, -497 American, 83.25% implied probability
The price -497 converts to 1.20 decimal odds and 20/99 fractional odds. Read as a probability it says the bookmaker prices this outcome at 83.25%, 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 83¢.
What -497 pays
A 100 stake at -497 returns 120.12 in total: your 100 back plus 20.12 profit. To win exactly 100 you would stake 497.00. The table covers the stakes people actually use.
| Stake | Profit | Total return |
|---|---|---|
| 10 | 2.01 | 12.01 |
| 25 | 5.03 | 30.03 |
| 50 | 10.06 | 60.06 |
| 100 | 20.12 | 120.12 |
| 500 | 100.60 | 600.60 |
| 1,000 | 201.21 | 1,201.21 |
Break-even and long-run results
The implied probability of -497 is 83.25%, and that number is also the break-even win rate: win more often than 83.25% 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% | -39.9% |
| 55% | -33.9% |
| 60% | -27.9% |
| 65% | -21.9% |
| 83% | -0.3% |
A price of -497 is deep odds-on. Bookmakers quote it when an outcome is close to a formality, and the margin they take is proportionally large at this end of the market. Sharp bettors tend to look at the other side of such a market, or at the exchange, where the same favourite is often available a tick or two better.
The vig at -497
If both sides of a two-way market were priced at -497, the implied probabilities would add up to 66.50% above 100%. That excess is the overround, or vig; as a share of stakes it is a 39.94% 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.
-497 on a betting exchange
Exchanges charge commission on net winnings, so the price you see is not the price you get. At 2% commission -497 is worth 1.197 decimal (-507 American); at 5% it drops to 1.191 (-523). Those are the bookmaker prices you would need to beat.
| Commission | Effective decimal | Effective American | Break-even |
|---|---|---|---|
| 2% | 1.197 | -507 | 83.53% |
| 5% | 1.191 | -523 | 83.95% |
Same price in other formats
Nearby prices
Nearby prices
Frequently asked questions
What does -497 mean in betting?
-497 is an American price. Positive numbers show the profit on a 100 stake; negative numbers show the stake needed to win 100. At -497 the implied probability is 83.25% and a 100 stake returns 120.12.
What is -497 in decimal odds?
-497 converts to 1.201 in decimal odds (usually shown as 1.20). Decimal odds are the total return per unit staked, so multiply your stake by 1.201 to get the return.
What is -497 as a fraction?
-497 is 20/99 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 -497?
A 100 stake at -497 wins 20.12 in profit and returns 120.12 including the stake. To win exactly 100 you would stake 497.00.
What win rate do I need at -497?
The break-even win rate equals the implied probability, 83.25%. Winning more often than that at this price is profitable over the long run; winning less often loses money.