reamly .org

ARCHIVE TOOL · MAX COMPRESSION

Create a 7z, smaller than zip

Compress files into a .7z (LZMA2) in your browser, far smaller than zip for text & raw data. Your Mac can’t make 7z; this can. Free, nothing uploaded.

Create a 7z
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How it works

Three simple steps

A quick overview before you start, the tool guides you through each step too.

  1. Add your files

    Drop in (or pick) any files, they never leave your device.

  2. Pick compression

    Normal or Maximum (LZMA2). Maximum squeezes compressible data the smallest.

  3. Download

    Get a .7z built entirely in your browser. Open it anywhere with a 7z tool, or our Extract page.

Questions & answers

Good to know

Common questions about size, privacy, and cost.

Why use 7z instead of zip?

7z uses LZMA2, which compresses text, CSV, logs, source code and other raw data substantially smaller than zip’s Deflate. For sending or archiving compressible files it makes a noticeably smaller download.

Can macOS make a 7z file?

Not on its own, the built-in Archive Utility only makes .zip. This tool creates a real .7z entirely in your browser using a WebAssembly build of 7-Zip, with nothing uploaded.

How do I open a 7z file?

On Windows use 7-Zip; on Mac use Keka or The Unarchiver, or just use Reamly’s Extract / Unzip tool, which opens .7z in your browser with no app to install.

Will my photos or videos get smaller?

No, JPEG, HEIC, PNG, MP4, MP3 and PDF are already compressed, so 7z (like zip) barely changes them. The big wins are on text, CSV, logs, databases, BMP/WAV and other uncompressed data.

Are my files uploaded anywhere?

No. Everything runs in your browser with WebAssembly, your files never leave your device. (Only the 7-Zip engine code is downloaded the first time.)

Is there a size limit?

No fixed limit, but everything is processed in memory locally, so very large batches may be slow or run out of memory on low-spec devices.

Does it cost anything?

No, it is completely free, no signup.

About

What Create a 7z does

Create a .7z archive, which is often far smaller than a zip for text and data. macOS can’t make 7z files on its own; Reamly does it in your browser with nothing uploaded.

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