.lzma

What is a .lzma file?

LZMA is a high-ratio compression algorithm — the engine behind 7z and xz formats.

Safe format
Type Archive
By Igor Pavlov
MIME application/x-lzma

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What is it

LZMA (Lempel-Ziv-Markov chain Algorithm) is the compression algorithm that makes 7z files so small. It typically compresses 20-30% better than gzip at the cost of slower compression speed. Decompression is fast and memory-efficient, which is why the algorithm found its way into countless applications beyond 7-Zip.

The .lzma extension is the raw compressed stream — no container, no metadata, just compressed bytes. In practice, you'll more often encounter LZMA inside container formats: .7z (7-Zip's archive), .xz (the modern replacement with checksums and metadata), and even .zip (which supports LZMA as a compression method).

XZ Utils has largely superseded raw .lzma files for standalone use, adding integrity checks and better streaming support. But LZMA the algorithm powers compression across the software world — from Android OTA updates to Debian package compression to UEFI firmware images.

Technical details
Full Name
LZMA Compressed File
MIME Type
application/x-lzma
Developer
Igor Pavlov
Magic Bytes
N/A
Safety
.lzma is a known, safe format. Compressed data. The compression format itself is safe.
What opens it
7-Zip
FREE Windows
xz (CLI)
FREE Mac / Linux
The Unarchiver
FREE Mac
FAQ
What's the difference between LZMA and XZ?
LZMA is the raw compression algorithm. XZ is a container format that wraps LZMA2 with integrity checks, metadata, and better streaming. For standalone compressed files, use .xz. LZMA is the engine; XZ is the car.
Is LZMA better than gzip?
LZMA compresses 20-30% better than gzip but is significantly slower to compress. Decompression speed is comparable. Use LZMA/XZ when file size matters more than compression time.
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