How many content keywords gives best performance? Is it really 3 or something else? My site has less information.
This is kind of hard to answer since you didn't give a link to your site, but my answer would be just how ever many are relevant. You don't want too many though, I'd max out at about 8 or 10.
I see some site wich have large keyword density and gain very hight (on 1st page) on Google Search. Some sites I can count up to 100 keywords.
all with depend on the strategy that you would use.. put as long as it is relevant to your site.. and you have to put lots of information to your site.. others say its 5-7..and max is 10..but all will depend on you..
Are you referring to how many different variations ok keywords are acceptable? I target 6 phrases based upon information from Google keywords tool and have them used in my content as well as anchor texts.
I don't count how many keywords I plan to target. I write my content the way I want it to read. That will determine how many keywords the page has. But yes, I do lots and lots of keyword research to make sure I'm using the best keywords for that topic, but I pay no attention to how many or how few keywords that page has. I don't let the tail wag the dog — that is, I don't let SEO overrule my content. I write for my readers, all the while "tweaking" that writing to include the best keywords in a way that flows nicely in readable content.