+391 Odds Explained
- Decimal
- 4.91
- American
- +391
- Fractional
- 391/100
- Implied probability
- 20.37%
- Polymarket
- 20¢
- $100 wins
- 391.00
- American
- +391
- Fractional
- 391/100
- Implied probability
- 20.37%
- Polymarket
- 20¢
- Profit
- 391.00
- Total return
- 491.00
4.910 decimal, +391 American, 20.37% implied probability
American odds of +391 mean
a 100 stake wins 391
. In decimal notation that is 4.91, in fractional notation 391/100, and the implied probability is 20.37%. On a prediction market the same price is a 20¢ share.
What +391 pays
A 100 stake at +391 returns 491.00 in total: your 100 back plus 391.00 profit. To win exactly 100 you would stake 25.58. The table covers the stakes people actually use.
| Stake | Profit | Total return |
|---|---|---|
| 10 | 39.10 | 49.10 |
| 25 | 97.75 | 122.75 |
| 50 | 195.50 | 245.50 |
| 100 | 391.00 | 491.00 |
| 500 | 1,955.00 | 2,455.00 |
| 1,000 | 3,910.00 | 4,910.00 |
Break-even and long-run results
The implied probability of +391 is 20.37%, and that number is also the break-even win rate: win more often than 20.37% 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 |
|---|---|
| 20% | -1.8% |
| 50% | 145.5% |
| 55% | 170.1% |
| 60% | 194.6% |
| 65% | 219.2% |
+391 is a longshot. The bookmaker prices the outcome at 20.37%, and the payout of 391.00 per 100 staked is the compensation for how rarely it lands. Longshots carry more margin than any other part of the market, which is why devigging methods disagree most at prices like this one.
The vig at +391
If both sides of a two-way market were priced at +391, the implied probabilities would add up to -59.27% above 100%. That excess is the overround, or vig; as a share of stakes it is a -145.50% 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.
+391 on a betting exchange
Exchanges charge commission on net winnings, so the price you see is not the price you get. At 2% commission +391 is worth 4.832 decimal (+383 American); at 5% it drops to 4.715 (+371). Those are the bookmaker prices you would need to beat.
| Commission | Effective decimal | Effective American | Break-even |
|---|---|---|---|
| 2% | 4.832 | +383 | 20.70% |
| 5% | 4.715 | +371 | 21.21% |
Same price in other formats
Nearby prices
Nearby prices
Frequently asked questions
What does +391 mean in betting?
+391 is an American price. Positive numbers show the profit on a 100 stake; negative numbers show the stake needed to win 100. At +391 the implied probability is 20.37% and a 100 stake returns 491.00.
What is +391 in decimal odds?
+391 converts to 4.910 in decimal odds (usually shown as 4.91). Decimal odds are the total return per unit staked, so multiply your stake by 4.910 to get the return.
What is +391 as a fraction?
+391 is 391/100 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 +391?
A 100 stake at +391 wins 391.00 in profit and returns 491.00 including the stake. To win exactly 100 you would stake 25.58.
What win rate do I need at +391?
The break-even win rate equals the implied probability, 20.37%. Winning more often than that at this price is profitable over the long run; winning less often loses money.