A horse race is a form of sport in which horses run against each other for money. There are many different types of races and many different rules for them. These rules vary from state to state but the vast majority of them are based on the British Racing Authority’s original rulebook, which has been adopted by most national racing organisations.
Race distance: The distance of a race is measured in furlongs, up to and including a mile. The most common distances are 6 furlongs and three-quarters of a mile.
Age: The most common age for a horse to race is five years old but there are some exceptions. A horse can also be a filly (a female) or a gelding (an older male).
Class: Races are classified by the level of ability of the horses in them. The highest levels are graded stakes. These races are usually more expensive to enter and can be accompanied by larger purses than other races.
Eligibility: A horse must be eligible to compete in a particular race before being entered, and this is determined by the age, sex and birthplace of the horse and the qualifications of the rider. There are a number of different ways to qualify for a horse race, but most often, the rider must be licensed by the local horse racing authority.
Stalls: The starting position of the horses in a Flat race is determined by the stall numbers that are drawn at random by Weatherbys (except for some top races, where the connections are allowed to select their own stall number). A horse that has a good draw will have a better chance of running well because it will be near the back of the pack and will not be at a disadvantage by the time the race starts.
Odds: The odds on a race are based on the total amount of money that is bet on all the horses competing in a race. The more money that is bet, the lower the odds on each horse to win a race.
The odds on a horse change every 30-60 seconds as more money is bet on the race. The higher the odds, the more likely a horse is to win.
Horses may have a steward inspect them at the start of a race to ensure they are eligible to be in the race and that they are not violating any rules. If an infraction is found, the stewards can ask that the race be suspended or that a re-run be held, and they can also decide to amend the order of finish.
Photo finish: In the event that two or more horses cross the finish line at the same time, a photograph of the race is examined by stewards to determine which horse crossed the line first. If a winner cannot be determined, the stewards will settle the race by dead heat rules.
Horse racing has largely existed under a patchwork set of rules across the dozens of states that host the sport, and the punishments for horse trainers and owners who violate these rules are often different from state to state. There is, however, a lot of overlap in the types of rules that exist.