Are you looking for a tool that checks keyword density or what? If that's what you are looking for, I'd be happy to let you know that keyword density is an obsolete ranking factor, so you should be spending time optimising your site for factors that matter.

If you use Wordpress, you can install Yoast, it is a full SEO tool for wordpress that is very useful. One of the best thinks that came with Yoast is the possibility of SEO optimise your blog posts.

Here is two images of my blog Startups That Rock, where I was creating a blog post with Yoast.

Yes it is called keyword organizer, I have it and that is what it does also much more. You should check it out. Hope this helps.

Thanks guys,
That is what I'm looking for, I'm starting with writing blogs post on my website but I dont use Wordpress yet.. So is there any other program?

Warrior

One tool I know which is best to check the keyword density in an article is Keyword Analyzer, it is best tool to find the keyword in article.

I have used this Keyword Density Checker a lot, especially when I am not using Wordpress. For using WP, yoast is perfect!

I prefer Market Samurai for check these keywords and all.