PWM Frequency Arduino Mega

What's the frequency of every PWM pin of the Arduino Mega? 'cause i've got a problem when multiplexing, I need to know te period of every cicle.

It's what you set it to. Perhaps provide more information, like your code.

i've got a problem when multiplexing

And what problem would that be?

Multiplexing PWM signals... interesting. Can you tell us more ?