Len56 wrote:
As an example, I am looking at a ceiling fan box that says that it is rated
for up to five #12 wires.

Does that include the bare ground wires that will be going into the box, or
is it just the conducting wires (such as the black and white wires)?

Yes. (But... )

You don't have to count wires under #14 from a fixture to wires in the box.

A wire originating in and terminating in the same box (ground from green
terminal of an outlet to box ground, for example) doesn't count.

A wire running thru a box w/o splice or tap counts as only one wire
(from which one can deduce the answer to the original question, btw).

And, of course, the limit for #14 would be higher than for #12 (probably
by one altho I didn't check tables).

There are other conditions/adjustments but those are the highlights that
are probably the pertinent ones for the application.

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