Curious to find out which is the world's biggest hamster breed? That and several interesting facts about the largest species of hamsters in this article.
Hamsters are some of the most popular house pets because they are tiny and relatively easy to care for. But are all hamster species tiny or are there any breeds that grow larger?
If we'd ask most hamster owners which is the largest breed of hamsters in the world, the majority would most likely give us a wrong answer.
Believe it or not, there is actually a hamster that's about double in size than any known species of domestic hamster. No, it's not a lab experiment or a hamster with a growth disorder. There is really a species of hamsters that can reach remarkable sizes.
World's Biggest Hamster Breed
Meet the European hamster.
The European hamster (scientifically known as Cricetus cricetus) is the largest species of hamster in the world. It is also known under names such as the common hamster, black-bellied hamster, or the Eurasian hamster. This is a wild species and as its name suggests, it is found in several regions of Europe and Asia.
European hamsters can reach some impressive sizes compared to domestic species. Thus, they can reach a weight between 7.8 and 16.2 oz (220-460g) and have a head-body length of 8-14 in (20 to 35 cm), plus a tail of 1.6 to 2.4 in (4-6 cm).  It is comparable in size to guinea pigs.
Unfortunately, this hamster breed has become critically endangered in recent years. Farmers consider them a pest, just like rats and other rodents. They have also been heavily trapped for their furs.
Biggest Domestic Hamster Breed
Although the European hamster is the largest hamster breed in the world, it is only a species that is very rarely kept in captivity as pets. So, I'm sure that many of you would also like to know which is the biggest breed of domestic hamsters.
I know many of you have already guessed. It's the Syrian hamster.
Syrian hamster (Mesocricetus auratus) is the largest breed of domestic hamsters. They are also known as golden hamsters and are among the most popular hamster breeds.
These hamsters can also be found in the wild, but their number has drastically declined in recent years due to humans trapping them, as well as the massive loss of their habitat.
A Syrian hamster typically weighs between 3.5 to 5.3 oz (100-150 grams) but the specimens from some breeders can surpass that range and go up to 6.2 7.9 oz (175–225 grams).
In terms of body size, most adults do not grow bigger than 6 in (15 cm) long. 
The European hamster is the world's biggest hamster breed, while the Syrian hamster is the largest species of domestic hamsters.
Unfortunately, both species are endangered in their natural habitat. Although the Syrian hamster is not so strongly threatened, being many specimens kept and multiplied in captivity, the European hamster is in much greater danger of extinction, the wild being often his only home.
I hope you found this article interesting and the next time someone asks you which is the biggest hamster breed, you will know the correct answer.