Some people think that programmers are smart and good at math. Nothing can be further from the truth, but it’s never late to learn. Honestly, I don’t think that an average front-end developer needs to know much about math or even algorithms or the networking protocols. It never hurts to know that, but it isn’t what most programmers do. Stack Overflow is our secret weapon, and we use it to solve 99% of the issues (and introduce a few more).
Math is kind of irrelevant for programmers. If you want to excel at job interviews, you better spend your time trying to memorize a bunch of algorithms and a Big O notation. Chances are, it won’t make you a better programmer, but there is a huge difference between being good at getting programming jobs and being good at programming so if it’s the first thing that you’re after, it’s clear that you shouldn’t worry about math.
That said, I believe that math skills can be beneficial to anyone and if you want to learn math or refresh your knowledge, Khan Academy is absolutely the best place to do that. I try to use it daily, but sometimes I take a break for a few months.