Border Collie Age Calculator
Your Border Collie's age in human years, breed-size adjusted, not the ×7 myth.
In human years
34
A 4-year-old medium dog is about 34 in human years.
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How the Border Collie ages
The Border Collie is a medium dog weighing about 30–55 lb, with a typical lifespan of 13–14 years. Like all dogs, the Border Collie matures fast early: about 15 human years by age one and 24 by age two, and then ages more gradually after that. A 5-year-old is roughly 39 in human years, and a 10-year-old about 64. This size-adjusted method reflects how medium dogs actually age, rather than the flat "multiply by seven" rule, which overstates the age of young pets and understates senior large breeds.
Quick reference
| Dog age | Human years |
|---|---|
| 1 | 15 |
| 2 | 24 |
| 5 | 39 |
| 8 | 54 |
| 10 | 64 |
Frequently asked questions
How old is my Border Collie in human years?
Enter your Border Collie's age above. As a guide, a medium dog is about 15 at 1 year, 24 at 2, and 54 by age 8.
Do Border Collies age faster than smaller dogs?
Smaller dogs age more slowly after year two and tend to live longer. That's why we adjust the curve by size instead of using ×7.
Keep going with the same pet
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