Hermit crabs molt for varying lengths of time depending primarily on their size:
- Small or tiny hermit crabs typically molt for a few days up to a couple of weeks.
- Medium-sized hermit crabs can take from a couple of weeks to about a month and a half or longer.
- Large or jumbo hermit crabs may molt for several months, sometimes up to 3-4 months or even longer, with some reports of jumbo crabs molting for as long as 6 months
The entire molting process includes preparation, shedding the old exoskeleton, hardening the new one, and recovery. The actual shedding is quick, but the surrounding stages take much longer. During this time, hermit crabs usually bury themselves in substrate for protection and remain inactive until their new exoskeleton hardens
. Hermit crabs generally molt about once every 18 months, but smaller crabs molt more frequently, while larger crabs molt less often
. In summary, molting duration ranges from a few days for small crabs to several months for large or jumbo crabs, with the process being longer for bigger individuals.
