Here's a handy little chart for newbies. It converts the odds of a horse to its corresponding percentage chance of winning. Sometimes it helps to think in terms of percentages that must fill a pie chart to equal 100%. Every horse gets a piece of the pie.

Let's say you have a 12 horse field.  The favorite is 2/1 (33%) and the second favorite is 3/1 (25%) for a combined total of 58%. That means the other ten horses in the field have a combined percentage chance to win of only 42%. That is not a realistic division of the "pie" and it can be exploited looking for value in your betting. The goal is to find the horse(s) that are being cheated out of their fair share of the pie in the betting pool.

Odds conversion to %      Rounding was used

ODDS      %      ODDS     %

1/9     .909     10-1     .091
1/5     .833     11-1     .083
2/5     .714     12-1     .077
1/2     .667     13-1     .071
3/5     .625     14-1     .067
4/5     .556     15-1     .063
    1     .500     16-1     .059
6/5     .455     17-1     .056
7/5     .417     18-1     .053
3/2     .400     19-1     .050
8/5     .385     20-1     .048
9/5     .357     25-1     .038
2-1     .333     30-1     .032
5-2     .286     35-1     .028
3-1     .250     40-1     .024
7-2     .222     45-1     .022
4-1     .200     50-1     .020
9-2     .182     60-1     .016
5-1     .167     70-1     .014
6-1     .143     80-1     .012
7-1     .125     90-1     .011
8-1     .111     100-1     .001
9-1     .100