Pick your kind of hamster and tell it how old yours is — or its birthday, or just the day it came home. You get how long that kind lives by every vet source that publishes a number, where yours is in that life, its life stage, and its age as a human comparison. The sources do not agree: for a Roborovski the Merck Veterinary Manual says three to four years and PetMD says two to three. You see both.
Syrian hamster
18–36 months (1½–3 years)
What each source says
A lifespan is what these hamsters usually reach, not a promise about yours. If yours has stopped eating, is losing weight, has a wet or dirty bottom, or is breathing hard, ring a vet who sees small animals today — at any age.
Lifespans checked 2026-09-25.
Quick answer: most pet hamsters live about two to three years, but the kind matters and the vet sources do not agree on the details. The Merck Veterinary Manual gives Syrians 18–36 months, Chinese hamsters 24–36, Russian dwarfs (Campbell’s and winter whites) 18–24 and Roborovskis 36–48. PetMD gives Syrians and Roborovskis 2–3 years, Chinese hamsters 1.5–3 and winter whites 12 months. PetMD counts any hamster of 1.5 years or more as elderly.
How to use it
Pick the kind of hamster, then tell it whatever you know: its age (18 months, or type 1 year 6 months), its birthday, or — for a hamster from a shop or a rescue — just the day it came home. You get the lifespan the Merck Veterinary Manual gives for that kind, every other source’s figure beside it, where yours sits in each range, its life stage, and its age as a human comparison. The result is in the link, so Copy link keeps it.
Why the sources disagree — and why you see all of them
The numbers come from different hamsters counted at different times. The Merck Veterinary Manual’s figures were revised in September 2026; PetMD’s article dates from April 2024; VCA’s hospital pages give one range for every hamster (“18 to 24 months on average, though some may reach 36 months”); the PDSA and Blue Cross say “about two to three years”. For a Syrian they roughly agree. For a Roborovski they do not: Merck says three to four years and PetMD two to three. For a winter white Merck says 18–24 months and PetMD twelve. An average of those would be a number nobody published, so the tool prints each one with its name on it and uses Merck’s for the headline, because it is the most recent veterinary reference.
How old is my hamster in human years?
There is no published “hamster years” rule — no equivalent of the dog-years tables vets argue over. So the tool does the only honest thing: it takes your hamster’s age as a share of its kind’s lifespan and sets that share against a human life, using the 79.0-year life expectancy the CDC published for the United States in 2024. A Syrian of 18 months is halfway through Merck’s longest figure, so it comes out at “about 40–79”: 40 if it will live the full three years, 79 if it stops at the shortest. It is a comparison to help you picture it, not biology, and the tool labels it that way.
The stages of a hamster’s life
- In the nest. The Merck manual: don’t disturb a mother and her babies for at least 7 days after birth; they are weaned at 21–28 days.
- A youngster. From weaning to 8 weeks. Merck: separate males and females before they’re 8 weeks old, or you will have babies of your own.
- An adult. From 8 weeks to a year and a half.
- A senior. PetMD: “a hamster that is 1.5 years old or older is considered elderly.” That is one rule for every kind — for a Roborovski or a Chinese hamster, Merck’s own figures put 1.5 years well before the end, and the tool says so.
If you don’t know how old your hamster is
You can’t read a grown hamster’s age off its weight or its coat. What you can know is the earliest it could have been born: every hamster is weaned before it is sold, and weaning happens at 21 days at the earliest, so choose The day it came home and the tool adds those three weeks and gives you an “at least”. A rescue or a breeder may know the birth date — it is worth asking.