I need to know the safe number of categories you can have on wordpress. I heard you can have 100 but will it run well with 100.
there is no "safe" number of categories. Chances are if you have 100 there will be some difference in performance, but any caching plugin should fix that
Ok first off, why would you even NEED 100 categories!? thats alot. and yes it will impact performance a little bit. but over all it should not make a huge difference. but either way, i would stay away from it unless you absolutely need that many. REASON: your site will look incredibly cluttered and busy. People dont want to see all that with pretty much nothing going on. so just stay away from that many categories. it will be better for your site overall.
theoretically 100 cats will slow your site down. But in actually, you shouldn't notice the diff from 10 to 100 categories.
IF you are going to have that much content you will need to do a lot of SEO to make sure all your content gets indexed.