How to Show Message Sizes in the Mac OS X Mail List

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Most email messages are small (some have a reported size of 0 bytes), but there are exceptions. To spot these exceptions at once when you look at a mailbox in Apple's Mac OS X Mail, you can include the message size in the list of displayed message attributes.

Why Would You Want to Know the Message Size?

You might want to know the message size in order to determine if a message has attachments or images within it. You might be looking for an especially long message or one with a lot of information or a large attachment. If your mailbox is full, you may want to delete these larger messages first in order to free up space on the mail server or to speed up the syncing of a new device.

Show Message Sizes in the Mac OS X Mail Mailbox List

To display the message size in the Mac OS X Mail message list:

  • Select View > Message Attributes > Size or View > Columns > Size from the menu in Mac OS X Mail.

To turn the display of message sizes off again, select the same menu item again.