Compress and extract .ezpz

Pack files and folders into one small .ezpz, or open a .ezpz someone sent you. Everything happens in this browser.

No upload

Drop a .ezpz file here

It opens in this browser. Nothing is uploaded.

The engine is ezpz 1.0.0, open source under the MIT License. GitHub

How to use it

  1. 1

    Pick a side

    Open a .ezpz to look inside and extract it, or make a new one from your own files and folders.

  2. 2

    Choose files or a level

    When opening, tick the files you want. When making one, pick how hard to compress and add a password if you like.

  3. 3

    Download

    The result appears on the next screen. Send this page’s address along with your .ezpz and the recipient can open it here too.

What .ezpz is

Our own archive format

.ezpz packs many files into one, like zip or 7z. It finds content that repeats across files and stores it once, then compresses with zstd, or at the highest levels with its own brain codec.

In our measurements the default level comes out about as small as tar.zst -19, and Smallest was smaller than 7z on all five data sets. The specification is public and the engine is open source under the MIT License.

Passwords and signatures

A password encrypts the contents and the file names together, so someone without it cannot even see what is inside. Archives signed with the command-line tool show their signing key here, so you can check who made them.

Every block and every file carries a hash. "Check for damage" reads them all and tells you whether anything changed on the way.

Common questions

What can open a .ezpz?+

For now, this page and the ezpz command-line tool for Windows, macOS and Linux on GitHub. Whoever you send one to can open it here for free, with nothing to install.

Which level should I pick?+

Default suits most files. Fast is quickest when there is a lot to pack. Max and Smallest make the smallest files but take much longer, both to make and to open.

Are my files uploaded?+

No. The ezpz engine (about 1.3 MB) comes to your browser, and packing and extracting happen there. Your files and your password never leave this device.

How big can the files be?+

Everything is held in the browser’s memory, so a computer handles about 1 GB at a time and a phone about 200 MB. For more, use the command-line tool.

Will a .ezpz made today still open later?+

Yes. The format was fixed at version 1, and every later version of ezpz will open version 1 files.