A lot of thought goes into naming a racehorse. Some people take inspiration from the horse’s pedigree, while others make it more personal, naming the horse after something special to the owner: a favorite boat, a treasured memory or the nickname of a close relative. Whatever the name, it must a dhere to The Jockey Club’s strict rulebook on submissions. First of all, there’s a character limit: no more than 18, including spaces. Second, names cannot be in any way vulgar or offensive. Other minor rules include that a name cannot consist of only initials or be comprised entirely of numbers. And if an owner wants to name their horse after a notable or famous living person, the naming rules require written permission from the subject. But for the most part, owners are free to choose whatever name they want, with one exception: It can’t match any of the names already used and registered in the Jockey Club’s racehorse database. According to the club registrar, at any given time there are about 450,000 active names in the database, so owners have to get creative. The horse racing industry’s main governing organization must approve the name in order for the thoroughbred to be registered to compete. Jockey Club registrar Rick Bailey has said the club rejects about 30% of submissions.  To help you get started choosing a name for your racehorse, this short quiz will generate a name based on some of your favorite things. Nelson Hsu, Nina Lin, Emilie Mutert / NBC More Triple Crown Coverage Kentucky Derby Apr 27 When is the Kentucky Derby? Here's everything to know at Churchill Downs in 2026 Kentucky Derby Apr 27 2026 Kentucky Derby horses: Here are the names, posts and jockeys for this year Triple Crown May 14, 2025 What is the Triple Crown and how many horses have won it? Editor’s Note: This story and interactive were originally published in 2018. ...read more read less