Skip to content

4.90 Decimal Odds Explained

Decimal
4.90
American
+390
Fractional
39/10
Implied probability
20.41%
Polymarket
20¢
$100 wins
390.00
Inputs
Results
Decimal odds4.900
American
+390
Fractional
39/10
Implied probability
20.41%
Polymarket
20¢
Profit
390.00
Total return
490.00

4.900 decimal, +390 American, 20.41% implied probability

A price of 4.90 carries an implied probability of 20.41%. That is the share of the time the bookmaker expects this outcome, margin included. In other formats it reads +390 (American), 39/10 (fractional) and 20¢ on a prediction market.

What 4.90 pays

Multiply the stake by 4.90 to get the total return. A 100 stake returns 490.00, of which 390.00 is profit. To win 100 in profit you would need to stake 25.64.

Payout by stake
StakeProfitTotal return
1039.0049.00
2597.50122.50
50195.00245.00
100390.00490.00
5001,950.002,450.00
1,0003,900.004,900.00

Break-even and long-run results

One divided by 4.90 is 20.41%: the implied probability, and the win rate at which betting this price neither makes nor loses money. The rows below show the return on stake at several win rates.

Return on stake by long-run win rate
Win rateReturn on stake
20%-2.0%
50%145.0%
55%169.5%
60%194.0%
65%218.5%

4.90 is a longshot price implying 20.41%. Bookmakers shade longshots more than any other price, so the true chance is usually a little higher than the implied figure suggests; the power and Shin devigging methods exist largely to model that shading.

Converting 4.90 by hand

Every other format follows from the decimal price in one step. Implied probability is one divided by 4.90, which gives 20.41%. American odds depend on which side of 2.00 the price sits: at or above 2.00, multiply (4.90 − 1) by 100 to get +390. The fraction is 4.90 − 1 written as a ratio and snapped to the nearest traditional price, 39/10. A prediction market simply quotes the probability in cents: 20¢.

The vig at 4.90

If both sides of a two-way market were 4.90, their implied probabilities would sum to -59.18% above 100%. That is the overround; as a share of stakes it is a -145.00% margin. The fair price with the margin removed is 2.00 on each side. The devig calculator does this for any market and any method.

4.90 on a betting exchange

Exchange commission comes off winnings, so 4.90 at 2% commission is really 4.822, and at 5% it is 4.705. The break-even win rate rises accordingly.

Effective odds on an exchange
CommissionEffective decimalEffective AmericanBreak-even
2%4.822+38220.74%
5%4.705+37121.25%

Same price in other formats

Same price in other formats

Nearby prices

Nearby prices

  • 4.65 · 4.65 · 21.5%
  • 4.80 · 4.80 · 20.8%
  • 4.85 · 4.85 · 20.6%
  • 4.95 · 4.95 · 20.2%
  • 5.00 · 5.00 · 20.0%
  • 6.50 · 6.50 · 15.4%

Frequently asked questions

What does 4.90 decimal odds mean?

Decimal odds of 4.90 return 4.90 for every 1.00 staked, including the stake, so the profit is 4.90 minus 1. The implied probability is 20.41%.

What is 4.90 in American odds?

4.90 decimal is +390 in American odds. Prices of 2.00 and above convert with (decimal − 1) × 100; prices below 2.00 with −100 / (decimal − 1).

What is 4.90 as a fraction?

4.90 is 39/10 in fractional odds: subtract 1 from the decimal price and express the result as a fraction.

How much does 100 return at 4.90?

100 × 4.90 = 490.00 total return, of which 390.00 is profit.

What win rate breaks even at 4.90?

1 / 4.90 = 20.41%. Win more often than that and the price is profitable; the bookmaker's margin means both sides of a market usually sit a little under fair.