All species grow at different rates. Arboreals will have a faster growth rate than terrestrials, and tropical species will have faster growth rates than desert species.

My Poecilotheria fasciata has gone from a 7/8" 2nd instar to 4-3/4" in under 3 years with 7 molts.

My Aphonopelma chalcodes has gone from 1/4" to 1-7/8" in 3.5 years and has had 6 molts.
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KJ Vezino
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