Text counter for guestbook

[Anon]

I'm interested for guestbook in http://www.4cm.com/guestbook/index.php?action=add

i have no idea how to make chars/text counter. in that site maximum chars allowed for user is 500 char. and while someone types text/chars in comments field the counter will increase/decrease.

is there any tutorial or idea how to make that counter? thanks for helping me.

[Anon]

That's Javascript, not PHP.
Try javascript.com or somethin'