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mail size increase with attched file and attachment size

  • 4 replies
  • 6 have this problem
  • 1 view
  • Last reply by Toad-Hall

Norman
Norman
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The issue: Mail size with no attachment is about 3,17 KB (3.251 Bytes) Mail with attachment 38,1 MB (38075102 Bytes) where the attached file is only 27,8 MB (27820247 Bytes) Why is mail with attachment this big and is even bigger when the attachment is bigger? I calculated 30 percent increase of the mail size itself from the attachment size. This causes problems with mails sending to an SMTP Server with a size limit from 20 Mb not able to send a 19 Mb file cause the mail itself is even larger. This is only in Thunderbird.

The issue: Mail size with no attachment is about 3,17 KB (3.251 Bytes) Mail with attachment 38,1 MB (38075102 Bytes) where the attached file is only 27,8 MB (27820247 Bytes) Why is mail with attachment this big and is even bigger when the attachment is bigger? I calculated 30 percent increase of the mail size itself from the attachment size. This causes problems with mails sending to an SMTP Server with a size limit from 20 Mb not able to send a 19 Mb file cause the mail itself is even larger. This is only in Thunderbird.

Chosen solution

Sending a binary file as a attachment increases its size by a third due to base64 encoding sending two 8-bit characters as three 7-bit ASCII characters.

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All Replies (4)

Toad-Hall
Toad-Hall
  • Top 10 Contributor
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Chosen Solution

Sending a binary file as a attachment increases its size by a third due to base64 encoding sending two 8-bit characters as three 7-bit ASCII characters.

Norman
Norman Question owner
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Toad-Hall said

Sending a binary file as a attachment increases its size by a third due to base64 encoding sending two 8-bit characters as three 7-bit ASCII characters.

Can we change it somehow?

Norman
Norman Question owner
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Norman said

Toad-Hall said
Sending a binary file as a attachment increases its size by a third due to base64 encoding sending two 8-bit characters as three 7-bit ASCII characters.

Can we change it somehow? Would be good if we could change the mail with postfix or a filter of some sort.

Toad-Hall
Toad-Hall
  • Top 10 Contributor
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You could zip the file to make it smaller. Or if an image reduce the dpi or size to make smaller file.

Read this info on sending large files as attachments

Info on FileLink for large attachments: