Birth Control Question: Timing?

Hi everyone! This is my first post, so I apologize if I'm doing this wrong. So I have been taking birth control pills since long before I actually needed them to prevent pregnancy. I have never been very strict about the timing, but I usually take them within a time frame of 3 hours. Now that I am sexually active, I was wondering if this is too large of a window. How strict are you guys (well girls, I guess) about taking your pills?