Create 7Z

Compress multiple files into a high-ratio 7z archive using LZMA2, running entirely in your browser. Files never leave your device — no install, no signup.

Conversions

About Create 7Z

Create 7Z bundles selected files into a .7z archive using a WebAssembly port of the 7-Zip LZMA2 encoder. 7z is the strongest mainstream-no-fees compression format thanks to LZMA2's large dictionary and range-coding scheme — typical size wins over ZIP are 30–60% on text, executables, log dumps, and source trees. AES-256 encryption is supported natively, so confidential bundles can go over email or messaging safely. The format is open and the 7-Zip reader is installed on most modern systems. The encoder runs in-browser; nothing is uploaded.

Best for

  • Archiving source trees and log dumps for long-term storage with maximum ratio
  • Sending confidential bundles over email/messaging with AES-256 inside the container
  • Anyone wanting the smallest archive without buying a proprietary tool

Pros

  • +LZMA2 — typically 30–60% smaller than DEFLATE ZIP on the same content
  • +Native AES-256 (no separate encryption tool needed)
  • +Open format; 7-Zip reader on Windows/macOS/Linux for free

Cons

  • −Slower than ZIP (LZMA2's larger dictionary eats CPU)
  • −Older corporate Windows machines without 7-Zip may need a one-time install

How to use Create 7Z

  1. 1

    Select or upload the source files from your local device storage.

  2. 2

    Specify conversion settings, options, or target output formats.

  3. 3

    Wait for the client-side browser logic to process the files securely.

  4. 4

    Download the finalized 7Z archive to your device.

Frequently Asked Questions

Why is 7z usually smaller than ZIP?
7z uses LZMA2 with a configurable dictionary up to 1.5 GB, plus strong range coding. ZIP's DEFLATE has a fixed 32 KB sliding window. The downside is 7z takes more CPU and RAM — that's why a 1 GB source archive can take a few minutes on a phone.
Can I password-protect a 7z archive?
Yes — set a password in the options; the encoder applies AES-256 directly in the container (no separate encryption tool needed). Don't lose the password — 7z AES-256 has no recovery backdoor.
Will recipients be able to open the .7z?
Most modern systems read .7z out of the box: macOS's Archive Utility since 10.15, most Linux desktops via file-roller, and Windows 11's built-in extractor handles .7z. Older corporate Windows machines need 7-Zip installed (free download).
Can I split the archive into multiple parts?
Not in the current release. Splitting (e.g. into 100 MB pieces) is on the roadmap. For now, pick a target file-size threshold and the encoder will compress as much as fits in the dictionary window you choose.
Are my files uploaded when making the .7z?
No. The LZMA2 encoder runs as WebAssembly inside your browser. Confidential source code, contract PDFs, financial exports — all stay local.

Related tools

FREE

100% Free

No hidden fees, no subscriptions, and no limits. Enjoy complete access to all features gratis.

SIGNUP

No Signup Required

Start converting immediately without creating an account or sharing email address.

PRIVACY

Private & Secure

Your files never leave your device. All processing is completed locally for maximum privacy.

BATCH

Batch Conversion

Convert multiple files simultaneously to save time. Fast and efficient multi-file queue.

LOCAL

Runs in Browser

Utilizes advanced client-side WebAssembly technology to process files directly inside your tab.

FORMATS

200+ Formats

Supports a wide variety of formats including images, documents, audio, video, and more.

USER REVIEWS

Create 7Z Quality Rating

4.8
25 reviews

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