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Horse Age Calculator – Horse Years to Human Years

Estimate your horse’s age in human years with this horse age calculator, based on a typical equine lifespan.

My tools →
Animal
years
months
Size (adult weight)

Small < 9 kg (20 lb) · medium 9–23 kg · large 23–41 kg · giant > 41 kg (90 lb)

Human years

–

Based on DNA methylation research in Labrador retrievers (UC San Diego, 2019). It ages young dogs faster than the classic chart.

Runs in your browser – your data never leaves your device Also available via our free API

Horse age chart in human years

Animal age Human years
1 year 2.9
2 years 5.7
3 years 8.6
5 years 14.3
10 years 28.6
15 years 42.9
20 years 57.1
25 years 71.4
30 years 85.7
35 years 100

Estimate based on a typical lifespan of 28 years compared with a human lifespan of 80 years. Individual animals vary.

How to use the Horse Age Calculator

  1. 1 Choose the animal.
  2. 2 Enter its age in years and months (for dogs, also pick the size).
  3. 3 Read the age in human years and the matching life stage.

How long do horses live?

Domestic horses commonly live 25 to 30 years, and ponies often live even longer. The calculator uses a lifespan of 28 years, so one horse year counts as just under three human years. A 20-year-old horse is roughly comparable to a person in their late fifties.

Life stages

  • Foal – up to 1 year; yearling between 1 and 2 years.
  • Young horse – 2 to about 5 years, the main period of training.
  • Adult – about 5 to 15 years, when most horses are in their prime.
  • Senior – generally from 15 to 20 years; many horses remain active well into their twenties.

Caring for an older horse

Dental check-ups become more important as teeth wear down, and senior horses may need easier-to-chew feed, extra attention to weight, and regular checks for conditions such as arthritis and PPID (equine Cushing’s disease).

Frequently asked questions

How old is a 20-year-old horse in human years?

About 57 human years, based on a typical lifespan of 28 years.

When is a horse considered a senior?

Usually from around 15 to 20 years of age.

Last updated: