Send a large ZIP file

Why won’t my ZIP file send by email?

Two reasons, often together. First, size: most providers cap a message at 20 to 35 MB as of October 2026, and a ZIP is usually made precisely because there was a lot to send. Second, security filters: archives are a classic way to hide malware, so mail services inspect them and refuse some.

Gmail, for example, does not let you send or receive certain file types, such as .exe, .bat, .js, .msi or .iso, even when they are inside an archive like .zip or .tgz. It also blocks password-protected archives that contain other archives, and documents with malicious macros. Company mail servers often apply stricter rules of their own.

Transfr does not block file types: archives, installers, disk images and scripts upload like any other file. The usual caution applies to your recipients: only open archives from people you trust.

How to send a large ZIP file with Transfr

1. 1

   Step 1

   Open Transfr

   Go to Transfr; there is nothing to install and no account to create.

2. 2

   Step 2

   Drop the archive

   Add your .zip, .7z, .rar, .tar.gz or any other archive, up to 100 GB per transfer. You can add several archives, or split volumes (.z01, .7z.001…), in the same transfer.

3. 3

   Step 3

   Choose link or email

   Copy the link, or let Transfr email up to 10 people with your message.

4. 4

   Step 4

   Add a password if needed

   Protect the download page with a password, or turn on end-to-end encryption for sensitive archives.

Do you even need to zip?

Often not. Zipping made sense when email only took single files. Transfr accepts whole folders and keeps their structure, so for photos, videos and documents you can skip the archive. It also lets your recipient preview files online and download only what they need, which a ZIP prevents.

You do not need to zip just to keep a folder tree, either: when your recipient clicks “download all”, Transfr hands them a single ZIP with the folders exactly as you sent them. Zip yourself only when the archive is the deliverable, or when you want to add archive-level encryption. Details on sending a folder without zipping and in should you zip files before sending.

Archives larger than 4 GB

The original ZIP format could not hold an archive, or a file inside it, larger than 4 GB. The ZIP64 extension removed that limit, and current tools (7-Zip, macOS Archive Utility, Windows, WinRAR) handle it, but very old unzip tools may fail on a big archive. If your recipient reports a damaged ZIP, ask them to try 7-Zip or The Unarchiver before you send it again.

Opening the ZIP on the other side

Standard ZIP files open without extra software on Windows, macOS, iPhone (in the Files app) and Android (in most file managers). 7z and RAR need an app such as 7-Zip on Windows or The Unarchiver on a Mac, so tell your recipient in the transfer message if you use them. Split archives only extract when every part is in the same folder: send all parts in the same transfer, which keeps them together.

If you send loose files instead, the recipient can still get a ZIP: “download all” on the Transfr download page packs everything into one archive with the folders kept.

Encrypted ZIP or encrypted transfer?

A password-protected ZIP (preferably AES-256 in 7-Zip or WinZip) protects the content wherever the file goes, but your recipient needs a compatible tool, and file names may stay visible depending on the format. An encrypted transfer protects the delivery itself:

• Password on the transfer: nobody can open the download page without it.
• End-to-end encryption: the archive is encrypted in your browser before upload, and file names are hidden from the server too. Read about end-to-end encrypted file transfer.
• Expiry and download limit: the link disappears after the date or number of downloads you choose.

For highly sensitive data, combine both: an encrypted archive sent through an end-to-end encrypted, password-protected transfer. More in secure file transfer.

How long does a big archive take to send?

At 50 Mbps of upload, a 2 GB ZIP takes about 5 minutes and a 20 GB archive about 53 minutes; at 100 Mbps, halve those. The upload retries automatically if the connection drops, and can resume after the page is closed if you add the same archive again within six days. See sending files over 2 GB and sending 10 GB.