Learn how to read the tote board. Odds for upcoming horse races are displayed on a large board at the race track, called the tote board. The board will display the number of the horse, the race, and the current odds. The odds can change in the minutes prior to a race, as money is placed on the various horses. For example, if you see a horse with odds of 3:1 it means that for every dollar you bet on that horse to win the race, you win three dollars. The shorter the odds, say 2:1, the more likely the horse will win. The longer the odds, say 30:1, the less likely the horse will win. A horse with long odds is called a long shot. When the horse you bet on wins, you also win back your stake. So, if you bet $1 on a 3:1 shot you get back your $1, plus your win of $3.
Work out the betting pool. The betting pool affects the odds and how much money is actually paid out to those who bet on the winning horse. For example, if race 1 has a betting pool of $1,000, it means that $1,000 dollars has been bet in total on the horses in that race.
Calculate the track's cut. Horse racing tracks take a cut from the betting pool, which ranges from 10 to 25 percent. This cut goes towards the profits of the track, paying prize money to the race winners and the running of the track. If the track you are at has a take of 10 percent, then the prize pool of $1,000 is actually $900. To work this out multiply 1,000 by 10 percent to get 100. Then subtract 100 from 1,000.
Take note of what portion of the prize pool has been bet on your horse. For example, of the $1,000 prize pool, $200 is bet on the horse you chose to win. Subtract $200 from the real prize pool of $900, giving you $700.
Calculate the odds for the horse you have bet on to win. Take the remaining prize pool of $700 and divide it by the amount of money that has been bet on your horse; in this example it is $200. The result of dividing $700 by $200 is $3.50. $3.50 means that the odds on your horse are 3:5. If you bet $2 at odds of 3:5 then you would win $3.20. The larger the percentage of the total prize pool bet on a particular horse means shorter odds and a lower pay out to those who have placed a bet on that horse to win. The lower the percentage of the total prize pool bet on a horse, the longer the odds, making the payout higher if that horse wins.