+128 Odds Explained
- Decimal
- 2.28
- American
- +128
- Fractional
- 32/25
- Implied probability
- 43.86%
- Polymarket
- 44¢
- $100 wins
- 128.00
- American
- +128
- Fractional
- 32/25
- Implied probability
- 43.86%
- Polymarket
- 44¢
- Profit
- 128.00
- Total return
- 228.00
2.280 decimal, +128 American, 43.86% implied probability
American odds of +128 mean
a 100 stake wins 128
. In decimal notation that is 2.28, in fractional notation 32/25, and the implied probability is 43.86%. On a prediction market the same price is a 44¢ share.
What +128 pays
A 100 stake at +128 returns 228.00 in total: your 100 back plus 128.00 profit. To win exactly 100 you would stake 78.12. The table covers the stakes people actually use.
| Stake | Profit | Total return |
|---|---|---|
| 10 | 12.80 | 22.80 |
| 25 | 32.00 | 57.00 |
| 50 | 64.00 | 114.00 |
| 100 | 128.00 | 228.00 |
| 500 | 640.00 | 1,140.00 |
| 1,000 | 1,280.00 | 2,280.00 |
Break-even and long-run results
The implied probability of +128 is 43.86%, and that number is also the break-even win rate: win more often than 43.86% 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 |
|---|---|
| 44% | 0.3% |
| 50% | 14.0% |
| 55% | 25.4% |
| 60% | 36.8% |
| 65% | 48.2% |
+128 is an underdog price: the bookmaker gives this outcome an implied chance of 43.86%, and the payout of 128.00 on 100 reflects it. Underdogs in this band are where public money and bookmaker margin often disagree, so it pays to compare prices across books before taking one.
The vig at +128
If both sides of a two-way market were priced at +128, the implied probabilities would add up to -12.28% above 100%. That excess is the overround, or vig; as a share of stakes it is a -14.00% 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.
+128 on a betting exchange
Exchanges charge commission on net winnings, so the price you see is not the price you get. At 2% commission +128 is worth 2.254 decimal (+125 American); at 5% it drops to 2.216 (+122). Those are the bookmaker prices you would need to beat.
| Commission | Effective decimal | Effective American | Break-even |
|---|---|---|---|
| 2% | 2.254 | +125 | 44.36% |
| 5% | 2.216 | +122 | 45.13% |
Same price in other formats
Same price in other formats
Nearby prices
Nearby prices
Frequently asked questions
What does +128 mean in betting?
+128 is an American price. Positive numbers show the profit on a 100 stake; negative numbers show the stake needed to win 100. At +128 the implied probability is 43.86% and a 100 stake returns 228.00.
What is +128 in decimal odds?
+128 converts to 2.280 in decimal odds (usually shown as 2.28). Decimal odds are the total return per unit staked, so multiply your stake by 2.280 to get the return.
What is +128 as a fraction?
+128 is 32/25 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 +128?
A 100 stake at +128 wins 128.00 in profit and returns 228.00 including the stake. To win exactly 100 you would stake 78.12.
What win rate do I need at +128?
The break-even win rate equals the implied probability, 43.86%. Winning more often than that at this price is profitable over the long run; winning less often loses money.