SharePoint 2010 - Checking Site Collection Quota Usage

This explains how to check the storage quota of a site collection..

Note: In order to check the storage quota you must be a site collection administrator or have been granted the "View Web Analytics Data" permission in the root site of your site collection.

Select Site Actions and then Site Settings

On the Site Settings page under the Site Actions heading, select Site Collection Web Analytics Reports

From the quick launch menu on the left, select Storage Usage under the Inventory heading to view current and historical information about your storage quota and usage.

Note: Files in the recycle bin are included in the site usage. You must empty the recycle bin to free up that space.