Send zip files, even large ones

What SendTheStuff will do with a zip email won't carry

SendTheStuff will take the zip as it is and hand you a link, so email's attachment cap and Gmail's blocked-file rules won't come into it:

• Big zips. SendTheStuff will take up to 5 GB per transfer, free, far past Gmail's, Outlook.com's or Yahoo's limit.
• Whatever's inside. SendTheStuff will accept any file type, so it won't refuse a zip for the kinds of files inside it.
• Loose files too. SendTheStuff will carry up to 1,000 files in one transfer, but the recipient will download them one by one. Zip them when they should arrive as one download.
• One link for anywhere. SendTheStuff will give you Copy, Email, Messages and Share buttons, so the same link works in email, chat or a text.
• Gone when it's done. SendTheStuff will keep the link working for 14 days, then delete the zip. Your cloud storage won't be touched.

How much zipping really saves, by file type

Zipping is often the first fix people try for a file that's too big to send. Whether it works depends almost entirely on what's inside. To find out, sample files of each common type were zipped and weighed for this guide.

"Saved" is how much smaller the zip came out than the files that went in.

The pattern is simple. Photos, video and PNGs are compressed already, so they have almost nothing left to squeeze. Office files and PDFs are partly compressed and shrink a little. Files stored raw, like text, WAV audio, uncompressed TIFF images and programs, shrink a lot.

Microsoft says the same about photos: zip several JPEGs, and the folder's total size will be about the same as the original collection of pictures.

How the test was run. Each set was zipped with standard Deflate compression at its default level, the method ordinary zip files use. The same sets were zipped again with 7-Zip's strongest zip setting, which saved under 2 percentage points more.

The samples were Windows' own wallpaper photos and system sounds, plus PDFs and Office templates installed with common apps. Windows program files and this site's own text files made up the rest. The PNG and TIFF images are those wallpapers re-saved. The video clips are short pans across them, encoded as H.264 and HEVC.

Near-blank images were left out, and so was a set of MP3s made from short system sounds, which were mostly silence. Two scan-style PDFs made from the photos were also left out, as unlike real scanner output.

So before you zip a 300 MB folder of holiday photos, expect a 295 MB zip. If it was too big to email before, it still is.

Why Gmail blocks some zips, whatever their size

Size isn't the only thing that stops a zip. Gmail looks inside it.

Gmail won't let you attach some file types, such as .exe, .bat, .js, .dmg, .apk, .msi and .iso. It blocks them when found within archives (like .zip or .tgz files), so zipping a program doesn't sneak it through. Its help also lists "Password-protected archives with archived content" among what it blocks.

Gmail's help names two messages for this:

• "Blocked for security reasons" is how its attachment help describes a file you can't attach, such as one ending in .exe.
• "This message was blocked because its content presents a potential security issue" is the error it gives for messages it blocks because they may spread viruses.

Google's own tip for a file you're sure is safe is to upload the file to Google Drive, then send it as a Drive attachment.

Zip size limits, app by app

Why the usual workarounds fall short

• A Drive link can stop working when it's popular. Google Drive shows "Too many users have viewed or downloaded this file recently" when a file gets lots of downloads at once. Google says it typically resets within 24 hours.
• Google itself points big zips elsewhere. For large files such as ZIP archives, Google advises dedicated hosting solutions rather than public Drive links.
• Cloud links use your storage. The zip counts against your Google storage, 15 GB free and shared across Drive, Photos, and Gmail.
• Splitting a zip into parts is fiddly. Some zip apps can split an archive so each part fits an email. The recipient needs every part, and an app that rejoins them.
• Zipping smaller rarely works. As the test above shows, photos and video barely shrink, so a zip of them stays about as big.

Until SendTheStuff launches

First, make the zip:

• Windows 11: right-click the files or folder, then select Show more options > Send to > Compressed (zipped) folder.
• Mac: Control-click > Compress. Several items become Archive.zip.
• iPhone: in the Files app, tap More > Select, choose the files, then More > Compress.

Then send it, by size:

1. Under 25 MB and nothing Gmail blocks inside: attach it to your email.
2. Over that, in Outlook.com: select Attach, then Upload and share, then Share link.
3. Over that, in Gmail: attach it anyway, and Gmail swaps in a Google Drive link. Pick "Anyone with the link" when it asks.
4. From an iPhone or Mac in Apple Mail: accept Mail Drop when Mail offers it.

Zip or no zip: when each makes sense

A zip still earns its place, just not as a way to shrink photos. Zip when:

• The recipient wants one file. A project folder with hundreds of small files is easier to download and keep as one zip.
• The folder structure matters. A zip keeps subfolders and file names together exactly.
• The files are text-heavy. In the test above, text, CSV and code files shrank by 45 to 91%.

Skip the zip when you're attaching a handful of photos or videos that already fit. It adds a step for the recipient and saves almost no space.

Opening the zip at the other end

Windows, Mac and iPhone all open a zip with built-in tools:

• Windows: right-click it and select Extract All.
• Mac: double-click it, and the contents appear beside it.
• iPhone: in the Files app, tap the ZIP file, and a folder with its files appears.

A SendTheStuff link will hand them the zip itself, to open the same way.

When it doesn't work

• The zip is still too big. Look at what's inside: photos and video barely shrink. Send it as a link instead of zipping harder.
• Gmail won't attach the zip. Something inside is a type Gmail bans, even zipped. Send it as a link.
• Gmail won't attach a password-protected zip. Its help lists "Password-protected archives with archived content" among what it blocks. Send it as a link, and share the password separately.
• The recipient sees "Too many users have viewed or downloaded this file recently". Your Drive link had too many downloads at once. Wait, or send the zip another way.
• The zip won't open. It may not have finished downloading. Download it again, and check there's enough free space for the unzipped files.