Limit character count in widgets

Hello, we are looking for either a little bit of code (php) or an optimal plugin to limit the character count on some of our widgets.

We ask because the way that we made our multisite network, it is easy for club owners to edit the content, but this is only through the widgets section. Some owners put far top much text in their bios. So we wanted to put a cap on the amount of text they will add.

Thanks for your help!