Crab or hermit crab?
How to tell them apart
Unlike most crabs, a hermit crab has a soft abdomen that it protects in a borrowed shell.
Quick answers
They differ on 2 of the 8 quick answers: awake when, do people eat it.
| Question | Crab | Hermit crab |
|---|---|---|
| What is it? | Crustacean | Crustacean |
| Carnivore? | Omnivore | Omnivore |
| Dangerous? | No | No |
| Domesticated? | No | No |
| Awake when? differs | Day & night | Night |
| Hibernates? | No | No |
| Kept as a pet? | Sometimes | Sometimes |
| Do people eat it? differs | Yes | No |
At a glance
| Question | Crab | Hermit crab |
|---|---|---|
| Found in differs | Oceans, Worldwide | Oceans |
| Habitat differs | Coast, Open ocean, Rivers & lakes | Coast, Open ocean |
| Size differs | Small | Tiny |
| Length differs | A few mm (pea crab) to a 4 m leg span (Japanese spider crab) | – |
| Legs | 10 | 10 |
| Covered in differs | Shell | Exoskeleton |
| Lives | In groups | In groups |
| Lives for differs | 3–30 years | 10–30 years |
| Can fly | No | No |
| Swims | Yes | Yes |
| Lays eggs | Yes | Yes |
About each
Crab
Armoured crustaceans with the tail tucked under the body, able to run sideways. The crab shape has evolved several separate times, a process called carcinisation, so crabs aren’t one natural group.
Hermit crab
About 800 species of crustaceans that protect their soft abdomen in empty snail shells. Most live in the sea, and some live on land.
Everything on the hermit crab page
Sources
Last reviewed . The answers and notes come from each animal's own page, where every source is listed.
How each answer is decided: How we answer. More look-alikes: Side by side.