Trouble with 'Big' Emails

Ever had trouble with an email that 'exceeds size limit', & you can't see why?

Tricky email sizing

That email with a 12 Mb attachment is larger than you'd think. Here's why.

Email sizes are expressed in bytes. File sizes are often in megabytes (Mb). There's a strange binary arithmetic twist whereby 1 Mb means 1,048,576 bytes, not 1,000,000 bytes. So much for metrication!

    • 12,582,912 bytes = 12 MB
    • 20,971,520 bytes = 20Mb

File size for an email includes all attachments plus the email body. Furthermore, files grow when they are attached to an email. Your email software can turn a 9 Mb attachment into 10.2 Mb.

A complex system

The email client (software) at sender's and recipient's end has its own email size limits. Mail servers also have sending limits. Your email has to meet everyone's specs. Email systems are not designed to transfer large volumes of data. Sending a lot of sizeable emails could take a whole system down.

It might suit you to attach large files, but the recipient might not be as happy. If your email chokes up their mailbox, it will stop other emails from reaching them.

Your email contacts use a range of good, bad & ugly email services. Don't risk undelivered messages & annoyed customers by bombarding everyone with unnecessarily big emails.

Reliable sending/receiving

  • As a general rule: 10 Mb is a safe maximum for most email services.
  • Scans can be monstrously large files. Limit the scan resolution if you can; 300 dots per inch is good enough for many documents.
  • For multiple attachments: send a few at a time.
  • Compress photos.
  • In the settings area of your mail software, you can set maximum email size. Search online for your email software's instructions. But remember that your email has to pass size limits at the receiver's end too.


If you have large files to share: what about loading them to your Bizazz website, then emailing the link to your friends, colleagues or customers? Here's how.

  1. Create a new webpage. This can be a non menu page: a private webpage that no one can access until you give them the direct link.
  2. For a PDF: upload your PDF document to the website backend using the Load File function in the webpage editor. Create a text or button link to the PDF on this webpage.
  3. For other filetypes: add content (photos, text, whatever) to the new webpage. Remember to first 'clean pasted text' in older Bizazz versions; Bizazz version 2 does this for you.
  4. Add other text etc. Format your webpage as you want.
  5. Publish the page. Email the link to the page.

Want to know more about bytes?

You can read more about file sizes here.