In finding link partners, one of the things that you may want to know is … how much traffic is that site getting? Not that this is the end-all in finding potential sites to link to you … but, knowing about traffic may allude to bigger issues, such as what their trust rank is.

But, if you are just trying to discover someone’s traffic, there are a few sources that you should take a look at:

• Alexa - This site has become completely unreliable over the years. I find that the numbers are frequently off. Alexa numbers are largely based on who has downloaded the Alexa toolbar. I would certainly look at Alexa if I am trying to find out how much traffic someone is getting. But, I would not rely on this information.
• Compete - I have found Compete.com to be the most reliable source for determining a site’s traffic. Compete has a paid service, but you can get quite a bit for free - probably, everything that you need. However, it is still not completely reliable. If I need to find a site’s traffic, here is what I do. I average Compete numbers with …
• Quantcast - Quantcast is a great site filled with information on numerous websites. They actually have a pixel that you can place on your site, and they can give you some very detailed and amazing demographic information on your visitors - if you have the pixel.

So, for me, personally, if I am trying to determine a site’s traffic, I look at Alexa, and I average the results from Quantcast and Compete. Bottom line.