Way to calculate ML odds into winning percentage?

**rkelly110** · 08-23-14, 08:39 PM

How To Convert Odds - The bettingexpert Academy

http://www.bettingexpert.com/blog/how-to-convert-odds

Betting odds reflect the probability of a particular event happening and understanding these probabilities is crucial to successful sports betting.

How To Convert A Percent To An Odds Ratio - Sciencing

http://www.ehow.com/how_8165670_convert-decimal-odds-percentage.html

Percentages measure the successful attempts per 100 tries. For example, a 20 percent chance of success means you will succeed 20 times out of 100. Odds ratios are reported as the number of failures per success. For example, an odds ratio of 4-to-1 means that four failures occur for each success, or one success per five attempts. If you have two probabilities, one measured as a percentage and the other as an odds ratio, you may have to convert to compare the relative probabilities.

**Maniac** · 08-23-14, 09:05 PM

I have setup an excel sheet to make the calculation easier on some of my other sheets, the calculation is below - for the purposes of my sheet B2 is the cell that I enter the US Style odds, so if you setup a similar sheet change all instances of B2 to whatever your input cell(s) is:

In the cell that you want the probability % in enter the following calculation:

=IF(B2>0,(100/(B2+100)),(-(B2)/((-(B2))+100)))

I am no excel wiz, so I am sure that this calculation can be streamlined by those who are wiz's, but this works fine for me and accounts for whether you end the price in using the - or + sign depending on if they are fav or underdog.

Using the above calculation, your example of Barcelona -980 comes out at a Probability of 90.74% chance of winning.

**Kababayan** · 08-24-14, 10:47 PM

Thank you for the responses.

**satana** · 08-31-14, 02:07 AM

100/decimal odds

**Venom OG** · 09-03-14, 09:31 PM

It's very easy. In your above example of -980 odds, all you have to do is add 100 to your number and then divide 980 by that number.

For example, 980+100 = 1080 so you would divide 980/1080 = 90.74%. So you would need Barcelona to have at least about a 91% chance of winning the game in order to make a bet on them profitable. Another more common example would be a line like Eagles -3.5 -120. In that case, the Eagles would have to have at least a 120/220 or 12/22 or 54.55% chance to cover the 3.5 in order to break even or make a profit.

Also, these numbers are not a team's chances of winning or covering. They are numbers based merely on a combination of the opinions of experts and the general public, and the number that a sportsbook thinks it can make the most money off of while assuming least possible risk. So, while the chances of winning an ATS bet averages out to 50% in the long run, the chances of winning any individual ATS bet vary greatly.