Can you renew your learners permit before it expires?

It can be but it will be about the same as your first time.

And this is for California?

It appears that you can renew it on the day that it expires, so if I were you I would make an appointment! It also appears that you have to the loud another application and pay the fees that you paid the first time when you got your learner's permit!! I went to dmv.ca.gov and searched renew my learner's permit and it gives you a detailed answer as to how to do that!! You have to basically do everything you did the first time!! And make sure you keep your first learner's permit it's the only proof you have that you have 6 months of experience driving evidently that they require!! Go to dmv.ca.gov and search "renew my learner's permit" and it tells you exactly what you need to do!!! Again do not throw away your first learner's permit you need to hang on to that and take it with you when you go to renew!