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How to tell how old your hamster is

how to tell how old my hamster is

If a question "How old is my hamster?" has crossed your mind, we might help you find the answer.

There are several things you can check to tell a hamster’s age:

  • eyes, ears and fur can help determine how old a baby hamster is;
  • size, weight and behaviour can give hints if a hamster is in his teenager or adult years;
  • activity level and health conditions can tell if a hamster is of an old age.

But unless the pet store consultant knows the exact birth date or a hamster is still a baby pup, there’s only so much you can tell from its behavior and appearance.

Age indicators also depend on hamster species, as the life expectancy varies. But we’ll give some information you can use if you really need to know how old your hamster is (to convert its age to human age, for example).


How to tell your hamster is 0-4 weeks old

Newborn hamsters are incredibly small, weigh under 3 grams, and their eyes and ears are shut.

  • You can tell that a hamster pup is under 10 days old if he still has no fur.
  • If his eyes are open and ears erect, you can be almost sure that this hamster pup is over 2 weeks old.

A hamster's baby life stage is quite short. Learn more about this creature’s life cycle.

If you see a baby hamster eating solid food and becoming less and less dependent on his mother, that’s a good sign he’s at least 3 weeks old.

How to tell your hamster is 1-5 months old

If you buy a hamster from a per store, it’s a good reason to believe he’s 6-8 weeks old. Maybe a bit younger as pups get separates from their mother at the age of 1 month. And sometimes even older, if some cute fella spends a longer time on a shelf waiting for his owner. 

Female and male hamsters are separated at this age as they reach sexual maturity (may seem too early, but it's due to a short lifespan hamsters have in general).

Another thing you can do is check the length and weight of the hamster. If he or she hasn’t reached their full grown size (see references in the next section) - he’s most probably an adolescent hamster under 6 months old.

How to tell your hamster is 6-18 months old

By the age of 6 months, hamsters reach adulthood. To check if your hamster is already adult, you can refer to the most popular hamsters’ size and weight:

Syrian Hamster adult size

  • Length: 5-7 in / 13-18 cm
  • Weight: 5-6 oz / 145-170 g

Roborovski Hamster adult size

  • Length: 1.8-2 in / 4.5-5 cm
  • Weight: 0.7-0.8 oz / 20-25g

Dwarf Campell’s Russian Hamster adult size

  • Length: 2-4 in / 5-10 cm
  • Weight: 1.4-2 oz / 40-60 g

Dwarf Winter White Russian Hamster adult size

  • Length: 2.7-3.5in / 6.8-9 cm
  • Weight: 2.5-3.2 oz / 70-90 g

Chinese Hamster adult size

  • Length: 3.2-5 in / 5-13 cm
  • Weight: 1-1.6 oz / 30-45 g

Adult hamsters live their life to the fullest. They are active, playful, sociable, and cute. And the more you care about your pet, the longer he will stay this way.

How to tell your hamster is over 20 months old

For a hamster, 2 years is already quite a long lifetime. And if you notice signs of your hamster getting older, like fur getting thinner, changes in activity level and appetite, you could tell he’s somewhere near that age. 

Except, perhaps, the Roborovski hamster. As one of the pet hamster breeds with the longest lifespan, his signs of getting old might appear after 24 months.

How old is my hamster: the cheat sheet

how to tell how old my hamster is cheat sheet

So now you can try and tell you hamster's age, at least approximately.