How to compress a heavy folder to send it by email
You try to attach a folder to an email and the client will not even let you select it. That is not a bug: email only understands loose files, and a folder is not one.
4 minute read
Why it has to be compressed
An attachment is a file. A folder is a structure with files inside it, and email cannot carry that. A ZIP solves both problems at once: it puts everything in a single file and takes up less space along the way.
How much less depends on what is inside. Text documents, spreadsheets and code can drop by 70%. Photos, videos, MP3s and PDFs already ship compressed and will barely move, though the ZIP is still useful for bundling them.
How to do it
Open the create ZIP tool and drag all the files in. Drop as many as you like, of any type.
Give it a name that means something to whoever gets it: "march-invoices" beats "files".
Press Create ZIP and download the result.
Attach that single file to the email. Whoever receives it only has to double-click: Windows, Mac, Android and iPhone all open ZIPs with nothing installed.
The limits you will run into
- Gmail: 25 MB per message. Above that it offers to upload to Drive and send a link.
- Outlook and Hotmail: 20 MB, with the same OneDrive alternative.
- Work email: usually stricter, between 10 and 20 MB. And the limit that counts is the recipient’s, not yours.
If it still will not fit once zipped
First look at what is taking up the space. It is almost always photos or videos, not the documents.
- If it is photos: run them through the compress image tool first. A 4 MB phone photo drops to 400 KB with no visible difference on screen.
- If it is scanned PDFs: compress those first, since that is where nearly all the weight sits.
- If it is videos: they are not going by email. Upload the video to Drive, WeTransfer or similar and send the link.
- If there is nothing to spare: make two ZIPs and send two emails. It is ugly but it arrives.
About passwords
A password-protected ZIP sounds like a good idea, but it causes more problems than it solves: many mail filters block protected ZIPs precisely because they cannot look inside, and the recipient needs the password through another channel. If the contents are sensitive, a private link is more practical.