Type the floor of the cage — or pick your glass tank — and see which published minimum it meets and which it misses: two countries’ laws, a US hamster club, the UK’s PDSA and Blue Cross, and the Swiss government’s own advice. They are not close. The legal minimums are about 1,800 cm²; the charities ask for 5,000. Most pages print one of them as if it were the only one.
Your cage
Legal in Austria and Switzerland — but under every welfare minimum
Every published minimum
A law’s minimum is the size below which keeping a hamster is an offence there — not a size anyone recommends. More floor and deeper bedding are never the problem.
Minimums checked 2026-09-25.
Quick answer: the UK’s PDSA and Blue Cross both ask for at least 100 × 50 cm of unbroken floor (39.4 × 19.7 inches, about 775 square inches) for any hamster, with 20–25 cm of bedding. The legal minimums are far smaller: 60 × 30 cm in Austria and 0.18 m² (for example 30 × 60 cm) for a Syrian in Switzerland — the Swiss government itself calls that “the absolute minimum” and advises at least half a square metre. The California Hamster Association uses 600 square inches.
How to use it
Measure the inside of the cage’s base, length and width — or pick your glass tank from the list — and say whether it is for a Syrian or a dwarf. You get which of the six published minimums it meets, how much more it would need for the charities’ 100 × 50 cm, and, if you add them, whether its height and your bedding depth are enough. Inches or centimetres both work, and a unit you type wins over the buttons.
Why there are six answers
Because the people who publish them are answering different questions. A law sets the size below which keeping a hamster is an offence in that country — Austria’s 2nd Animal Husbandry Ordinance, Switzerland’s Animal Welfare Ordinance. A charity says what a hamster needs to live well; the PDSA and Blue Cross both settled on 100 × 50 cm. A club — the California Hamster Association — sets a standard for its members. The Swiss government publishes both the law and, separately, the advice that the legal size is not enough. An average of those would be a number none of them published, so the checker shows every one with its name on it.
Only the floor counts
A tall cage with three shelves has the floor of its base, not of its shelves. The PDSA recommends a single-level cage, and Blue Cross advises against elaborate tube systems — levels add climbing, not room to run and dig. That is why the checker asks for the base only.
What about a 40-gallon tank?
The 40-gallon breeder is the tank people ask about most, and by Aqueon’s own chart it measures 36 3⁄16 × 18¼ inches on the outside — about 660 square inches. That meets the California Hamster Association’s 600 and both legal minimums, but it is short of the PDSA and Blue Cross 100 × 50 cm on both sides. In fact no tank on Aqueon’s chart meets it: the deepest front to back are 18½ inches (47 cm) against the charities’ 50 cm, so a 75-gallon has the floor area but not the width. The checker says so for every tank on the list.
Bedding and height
A hamster digs, and the published minimums for how deep it should be able to dig vary as much as the floors do: 5 cm in Austrian law, 15 cm in Swiss law, 20 cm at Blue Cross, 25 cm at the PDSA — and 30 to 80 cm, which the Swiss government calls ideal. The cage has to be tall enough to hold that bedding below the bars: Blue Cross asks for 50 cm, Austrian law for 40, and the Merck Veterinary Manual for at least 15 cm, with 20 or more better.