What is the approximate length of a catepillar?

Question

What is the length of an insect...

Answer 1

Insects vary in size from microscopic to over a foot in length.  They can be 1/10000 of a gram to over two pounds.  A caterpillar depends on the size of the species of butterfly or moth.  Some Lepidopterans (butterflies and moths) can be less than an inch in wing span and 1/2 inch in body length and others can be several inches in wingspan with 2-3 inches of body length.  The caterpillars would be corresponding varied in size depending upon the species.

Answer 2

Are you serious? The species might come into play I think.

Answer 3

A caterpillar?  A couple of inches, but every caterpillar is different and every caterpillar gets bigger as it eats and eats.  

What is the length of an insect?  What insect?  There are millions or perhaps billions of different types of insects and they're all different lengths!  Anything from a few centimeters to several inches in length.  Other invertebrates can get larger than a foot or so in length, like certain centipedes or millipedes.