I have been doing researches regarding alexa’s accuracy in the past 2 weeks. I did an experiment between 2 sites.

 The experiment

I took one site of mine which is getting over 20,000 unique visits daily and another one which is getting 200 visits/daily. I am not going to give the exact url’s of the site’s, but let A be the site with 20,000 UV/day and B the site with 200 UV/day.

I read guides, posts etc. regarding optimization of one’s alexa rank. I used those optimization tactics on site B and left site A apart. The optimization tactics were basically consisting in placing the Alexa button on your site, installing the alexa toolbar and using alexa redirect for getting on your site.

The result

Site A, which gets 100x more visitors per day then site B has a HIGHER alexa rank then site B. It means that according to alexa, site B gets more traffic then site A.

Conclusion

Alexa is a bad tool of measuring your site’s traffic. It might be a good traffic ratio, but in my case it isn’t. Do not use alexa for determining traffic of one site. But, if you insist on optimizing your alexa rank use those tips I mentioned above.

I hope this was somehow convinceive :D

*If requested, I can bring proofs of traffic for site A and site B.