-340 Odds Explained
- Decimal
- 1.29
- American
- -340
- Fractional
- 5/17
- Implied probability
- 77.27%
- Polymarket
- 77¢
- $100 wins
- 29.41
- American
- -340
- Fractional
- 5/17
- Implied probability
- 77.27%
- Polymarket
- 77¢
- Profit
- 29.41
- Total return
- 129.41
1.294 decimal, -340 American, 77.27% implied probability
American odds of -340 mean
you risk 340 to win 100
. In decimal notation that is 1.29, in fractional notation 5/17, and the implied probability is 77.27%. On a prediction market the same price is a 77¢ share.
What -340 pays
A 100 stake at -340 returns 129.41 in total: your 100 back plus 29.41 profit. To win exactly 100 you would stake 340.00. The table covers the stakes people actually use.
| Stake | Profit | Total return |
|---|---|---|
| 10 | 2.94 | 12.94 |
| 25 | 7.35 | 32.35 |
| 50 | 14.71 | 64.71 |
| 100 | 29.41 | 129.41 |
| 500 | 147.06 | 647.06 |
| 1,000 | 294.12 | 1,294.12 |
Break-even and long-run results
The implied probability of -340 is 77.27%, and that number is also the break-even win rate: win more often than 77.27% 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% | -35.3% |
| 55% | -28.8% |
| 60% | -22.4% |
| 65% | -15.9% |
| 77% | -0.4% |
At 77.27% 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 77.27% of these bets just to stand still, and one loss wipes out several wins.
The vig at -340
If both sides of a two-way market were priced at -340, the implied probabilities would add up to 54.55% above 100%. That excess is the overround, or vig; as a share of stakes it is a 35.29% 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.
-340 on a betting exchange
Exchanges charge commission on net winnings, so the price you see is not the price you get. At 2% commission -340 is worth 1.288 decimal (-347 American); at 5% it drops to 1.279 (-358). Those are the bookmaker prices you would need to beat.
| Commission | Effective decimal | Effective American | Break-even |
|---|---|---|---|
| 2% | 1.288 | -347 | 77.63% |
| 5% | 1.279 | -358 | 78.16% |
Same price in other formats
Nearby prices
Nearby prices
Frequently asked questions
What does -340 mean in betting?
-340 is an American price. Positive numbers show the profit on a 100 stake; negative numbers show the stake needed to win 100. At -340 the implied probability is 77.27% and a 100 stake returns 129.41.
What is -340 in decimal odds?
-340 converts to 1.294 in decimal odds (usually shown as 1.29). Decimal odds are the total return per unit staked, so multiply your stake by 1.294 to get the return.
What is -340 as a fraction?
-340 is 5/17 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 -340?
A 100 stake at -340 wins 29.41 in profit and returns 129.41 including the stake. To win exactly 100 you would stake 340.00.
What win rate do I need at -340?
The break-even win rate equals the implied probability, 77.27%. Winning more often than that at this price is profitable over the long run; winning less often loses money.