Most SEO people already know about ranks.nl, but I wanted to share it just in case some of our readers here were unaware. This is a GREAT tool for finding out keyword density, if you have broken links, comparing two files for changes, and a ton of other things. Most of the tools are free to use to a point and can really help you determine problems with your site.

I would take special note of the keyword density and proximity tools. I haven’t found a better tool for checking keywords on the Web yet. Most software packages don’t even include that level of detail when checking densities. Definitely take a look at their tools. I find them really helpful during the optimization process.