Horse Age 

The following table summarizes how to convert horse years to human years, and is based on the Equine-Human Maturity Evaluation.

Horse Age Equivalent Human Age Human equivalent Change
0 (newborn) 2 years  
1 year 8 years 1st horse year = 6 human years
2 years 13 years  2nd horse year = 5 human years
3 years  17 years 3rd horse year = 4 human years
4 years 20 years 4th horse year = 3 human years 
5 to 24 years 21 to 70 years  After 4th year, each horse year = 2.5 human years 

The above table is an average of different horse breeds, based on a well-kept domestic horse. It uses an average horse lifespan of 24 years and an average human lifespan of 70 years. Wild horses and poorly kept horses have a much shorter lifespan, while some breeds (e.g. Arabian and many pony breeds) have a longer lifespan. To allow for different breed lifespans, simply use the following calculator:

  • change the number in green (under 'Normal LIfe Expectancy' to the normal lifespan for your breed of horse,
  • then click on the 'update' button to calculate the equivalent human ages for this lifespan (this calculator uses an average human lifespan of 74 years).
  • You can click on the 'print' button to print the values out.

Normal Life Expectancy Horse Age Human Years


Convert Excel spreadsheet to online form

 Oldest Horses

The oldest living horses include:

  • Old Billy. Born in England in 1760, hedied on 27/11/1822 at the age of 62 years. He lived as a barge horse that pulled barges up and down canals, reportedly actively working until the age of 59. Old Billy was said to look like a big cob/shire horse
  • Sugar Puff. The oldest living pony in modern times. Died in 2007 at the age of 56 years.


The terminology used to describe horses of various ages is as follows:

  • Foal: Al horse (either male or female) less than a year old. A nursing foal is sometimes called a suckling and a foal that has been weaned is called a weanling. Most domesticated horses are weaned at 5 to 7 months of age, although commercial breeders often wean much earlier.
  • Yearling: A horse (mare or female) that is between one year old and two years old.
  • Colt: A male horse under the age of four. Some people use this term for both female and male horses under four, but correct use is for a male only (see Filly below).
  • Filly: a female horse under the age of four.
  • Mare: An adult mare. Some organisations define this as four years old and others as three years old.
  • Stallion. A male horse over four years old, which has not been castrated.
  • Gelding. A male horse which has been castrated, regardless of age.
  • Ridgling (or rig). A male horse which has has an undescended testicle or has been improperly castrated. It will appear to be a gelding, but will have some of the behaviours of a stallion.
  • Veteran. A horse over 15 years of age.

Some countries and organisations use different ages than the above definitions. For example, in thoroughbred racing a colt is defined as a male under five years (rather than under four years) and a filly as a female under five years (rather than under four years). 


Equine-Human Maturity Evaluation. The basis for the above calculators, it provides the intellectual basis for the above calculators and additional information on matching horse and human maturity.

Horse Aging. Explanation of the main factors which determines how fast a horse ages, the duration of its working life, and its expected lifespan. It also provides guidance on how to help your horse live longer and be healthier.

Old Horse. Care and treatment of older horses.