These Top 50 Free Classified Ads sites have at least a PR 4. Using PR Checker and Alexa, I've spent hours and hours in compiling and validating this list so as to bring ease to marketers, beginners or experienced alike. All you have to do is register with them and post your free ads.

There may be no scientific study in coming up with this list, but if you post in these free classified ads site, especially those with PR 7, you'll see the science of powerful backlinks.

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