-820 Odds Explained
- Decimal
- 1.12
- American
- -820
- Fractional
- 5/41
- Implied probability
- 89.13%
- Polymarket
- 89¢
- $100 wins
- 12.20
- American
- -820
- Fractional
- 5/41
- Implied probability
- 89.13%
- Polymarket
- 89¢
- Profit
- 12.20
- Total return
- 112.20
1.122 decimal, -820 American, 89.13% implied probability
-820 is an American price:
the minus sign marks a favourite, and the number is the stake needed to win 100
. Every other format describes the same chance: 1.12 decimal, 5/41 fractional, 89.13% implied probability, 89¢ on Polymarket.
What -820 pays
A 100 stake at -820 returns 112.20 in total: your 100 back plus 12.20 profit. To win exactly 100 you would stake 820.00. The table covers the stakes people actually use.
| Stake | Profit | Total return |
|---|---|---|
| 10 | 1.22 | 11.22 |
| 25 | 3.05 | 28.05 |
| 50 | 6.10 | 56.10 |
| 100 | 12.20 | 112.20 |
| 500 | 60.98 | 560.98 |
| 1,000 | 121.95 | 1,121.95 |
Break-even and long-run results
The implied probability of -820 is 89.13%, and that number is also the break-even win rate: win more often than 89.13% 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% | -43.9% |
| 55% | -38.3% |
| 60% | -32.7% |
| 65% | -27.1% |
| 89% | -0.1% |
A price of -820 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 -820
If both sides of a two-way market were priced at -820, the implied probabilities would add up to 78.26% above 100%. That excess is the overround, or vig; as a share of stakes it is a 43.90% 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.
-820 on a betting exchange
Exchanges charge commission on net winnings, so the price you see is not the price you get. At 2% commission -820 is worth 1.120 decimal (-837 American); at 5% it drops to 1.116 (-863). Those are the bookmaker prices you would need to beat.
| Commission | Effective decimal | Effective American | Break-even |
|---|---|---|---|
| 2% | 1.120 | -837 | 89.32% |
| 5% | 1.116 | -863 | 89.62% |
Same price in other formats
Nearby prices
Nearby prices
Frequently asked questions
What does -820 mean in betting?
-820 is an American price. Positive numbers show the profit on a 100 stake; negative numbers show the stake needed to win 100. At -820 the implied probability is 89.13% and a 100 stake returns 112.20.
What is -820 in decimal odds?
-820 converts to 1.122 in decimal odds (usually shown as 1.12). Decimal odds are the total return per unit staked, so multiply your stake by 1.122 to get the return.
What is -820 as a fraction?
-820 is 5/41 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 -820?
A 100 stake at -820 wins 12.20 in profit and returns 112.20 including the stake. To win exactly 100 you would stake 820.00.
What win rate do I need at -820?
The break-even win rate equals the implied probability, 89.13%. Winning more often than that at this price is profitable over the long run; winning less often loses money.