How old is a 26 year old horse in human years?

To convert a horse's age to human years, a common method is to consider the first two years of a horse's life as equivalent to about 6 years in human terms, and then each subsequent year as roughly equal to 4 human years. Thus, a 26-year-old horse would be approximately 6 + (24 x 4) = 102 human years old. This is a rough estimate, as individual horses may age differently based on breed and health.