http://www.alexa.com/site/ds/top_500

Know Alexa traffic rankings for your site or browse for top ranking websites for different regions and categories. The rankings are calculated based on the details collected from the users of alexa toolbar and other sources for a period of 3 months. The rankings are provided only for top level domain and not for any internal sub pages. To know your traffic history just input your domain name and click get traffic details.

The graph shows following important details:

Reach: It measures the number of users in percentage who visit a given site.

Page views: Measures the number of pages viewed by site visitors.

Rank: The traffic rank is based on 3 months of traffic data from alexa toolbar users and from other sources, with a combined measure of page views and reach.

You can compare your rankings against your top 5 competitors by adding their domain names on the top side of graph. Below the graph you can see the weekly average, monthly average and fluctuations observed over a period of time.