Managing Your iCloud Storage on Your iMac
Apple knows that you’re curious about how much space you’ve taken up in your personal iCloud. To monitor your iCloud storage on your iMac, click the Manage button at the bottom-right corner of the iCloud System Preferences pane. On the sheet that appears, you can see how much space you’re using for document and data storage.
Click the data type in the left column, and iCloud displays the amount of storage space that’s being used for that data. Here, you can see the amount taken by an iPhone backup. Other items that might appear in this sheet include Mail and selected iPad and iPhone apps that support iCloud.
If you find yourself running out of iCloud storage space, delete any stored item by selecting it in the list at the right side of the sheet and clicking Delete.
And if you need more elbow room than 5GB, Apple is happy to provide 50GB, 200GB, or even a whopping 1TB of additional storage for a monthly subscription fee of 99 cents, $2.99 or $9.99, respectively. (Naturally, these prices are subject to change.) Click the Manage button on the iCloud pane in System Preferences and then click the Buy More Storage button to subscribe.