The seven year itch: another dog myth bites the dust

Article about dog years equivalence in human age
By Laure-Anne Visele, July 2012

One dog year = seven human years = zero truth

If a rule of thumb is too convenient, it’s just too good to be true. The ‘seven-year rule’ is no exception.

Here’s a more intelligent way to estimate your dog’s maturity in human years.

seven-year itch, geddit?

Before we dive in: bear in mind this is not hard science. It’s just a little trick to help you estimate your dog’s social maturity. Also, these periods are not written in stone, and there will be quite a bit of variation from dog to dog

This is particularly relevant around the 12-month mark, when many owners think they are dealing with a sweet puppy when it’s more like a raging teenager.

The following rule was given to me by Stan Rawlinson, the original Dog Listener. It is one of my favourites:

  • Between 0 and 16 weeks in dog years = between 0 and 5 years in human years
  • 12 months = 15 human years. Think teenage attitude and all that goes with it.
  • 24 months = 25 human years.
  • Every 1 year thereafter = add 4 human years per year
This might help you visualise it:

Click on the graph for full display - ©2012 Canis bonus - please do not reproduce without permission

Sexual versus social maturity

These two concepts are quite important when discussing the maturity of dogs:

  • Sexual maturity = physiological ability to procreate. It ranges between 6 to 15 months, with most dogs reaching it between 7 and 10 months (Houpt, 1991). This may be later larger breeds.
  • Social maturity = age around which the dog’s temperament has stabilised, the age by which it has reached its adult social maturity. It begins between 18 months and 24 months, give or take, depending on the breed.

Breed differences

Of all animal species, dogs are by far the most varied among themselves in terms of size and weight. The average weight of a chihuahua is 40 times lighter than the average weight of a St Bernard (and a mere 20 times lighter than that of a Great Dane).


Larger breeds take longer to reach their full size and sexual maturity. Larger breeds will also show signs of ‘wear-and-tear’ sooner. So their life expectancy is often in the region of 10 years, as opposed to 15 for smaller dogs.

My point is: adulthood (between the childhood and the geriatric period) is much reduced for large breeds. But again, this rule of thumb is mainly concerned with behaviour, not physical maturity.

Other methods

A contact of mine pointed out this method as an alternative. Looks good to me!

Courtesy of the German Shepherd Dog Community on Facebook


I love to read your comments, so leave me your thoughts any time. I’d particularly like to hear from you if you have a view to share about:

  • Social and sexual maturity in canids; and/or
  • Another formula for estimating a dog’s maturity; and/or
  • A story about your sweet 12-month-old ‘puppy’.

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