How to know the traffic of a website?

To know what is the traffic of his own website is easy with a tool like Analytics or the statistical service of the host, but how to evaluate the traffic of another site for which we do not have access to the statistics?

There are three simple tools to access statistical data from other sites. No one gives absolutely accurate values, but they are nevertheless useful because they all can make the difference between a few visited or popular site.

Google Ad Planner

This online service aimed to advertisers provides the number of monthly visits that a site receives based on tracking cookies. However all users do not allow on their computer the opportunity to place cookies and all sites did not generate them either.

The Ad Planner values roughly correspond to the actual site traffic. The service also shows the number of page views and the average time spent on the site by a visitor.

Google Trends for Website (now closed)

It was a tool for comparison and a trend indicator. It displayed the evolution of Web sites traffics over time, and superimpose the graphs of several sites for a better comparison. The service indicated the percentage of countries and also the other sites visited by same users.

Alexa

It is the most known service and it is not considered the most reliable. This service advantages outrageously sites in English.

Alexa does not show traffic in numbers but in position on the Web instead. Thus we see that Yahoo.com is the most visited site. The higher is the traffic, the higher values are close to reality. As Trends, it can overlay graphics for several sites to compare them. And as Ad Planner it indicates the average number of pages viewed and the time spent on the site by a visitor.