How to Tell a Horse's Age by Its Teeth

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Care of Horse Teeth

Because horse's teeth grow throughout most of their lifespan and may not wear evenly, your horse will need to be checked by a veterinarian or equine dentist about once per year. Your horse may need to be floated, removing by filing any sharp edges or hooks that will prevent him from chewing properly and holding a bit or wearing a hackamore comfortably.

Detailed Diagrams and Explanations of Horse Teeth

While this is a general description of aging horses by their teeth several university agricultural extensions have detailed fact sheets with diagrams that show horse's teeth at every stage of life. The PDF file from the University of Nevada Cooperative Extension is quite good and easy to print out so you can take it to the barn and compare pictures to actual teeth. The University of Missouri has a similar online resource with diagrams and explanations.