How to extract xz files in Linux

A .xz download can be either one compressed file or a tar archive that needs directory extraction. Treating both forms the same can leave a compressed stream in place or unpack archived paths into the wrong directory, so identify the file shape before writing output.

A plain .xz file contains one compressed data stream. xz --decompress recreates the original file and normally deletes the compressed input after a successful run, while --keep preserves the archive for repeatable extraction or audit trails.

A .tar.xz file stores a tar archive inside xz compression. GNU tar can list and extract normal compressed archive files without adding --xz, though --xz or -J is still useful when compressed archive data comes from a pipe. Use a dedicated restore directory when the archived paths may overlap with existing files.

Related: Extract .tar.gz files
Related: Extract tar.bz2 files
Related: Extract 7z files

Steps to extract xz files in Linux:

Identify the archive format before extracting it.
```
$ file project-notes.txt.xz project-backup.tar.xz
project-notes.txt.xz:  XZ compressed data, checksum CRC64
project-backup.tar.xz: XZ compressed data, checksum CRC64
```
The file command confirms the compression format, but a .tar.xz archive still needs a tar listing step to show the stored file names. Files that end in .txz are the same kind of tar archive compressed with xz.

List metadata for the plain .xz file.

$ xz --list project-notes.txt.xz
Strms  Blocks   Compressed Uncompressed  Ratio  Check   Filename
    1       1        124 B         58 B  2.138  CRC64   project-notes.txt.xz

xz --list prints size and integrity-check details without writing any output files.

Decompress the plain .xz file while keeping the original archive.
```
$ xz --decompress --keep project-notes.txt.xz
```
No output means xz finished without reporting an error. Omit --keep only when the compressed source file should be removed after successful extraction.
Verify the restored file and retained archive.
```
$ file project-notes.txt project-notes.txt.xz
project-notes.txt:    ASCII text
project-notes.txt.xz: XZ compressed data, checksum CRC64
```
If the target filename already exists, xz stops instead of overwriting it unless --force is added deliberately.
Preview the .tar.xz archive before extracting it.
```
$ tar --list --file project-backup.tar.xz
project-backup/
project-backup/reports/
project-backup/reports/report.txt
project-backup/beta.log
project-backup/alpha.txt
```
Current GNU tar releases auto-detect compression when reading a normal archive file, so --xz is not required here. If the archive is being read from a pipe instead of a file, add --xz or -J to tell tar which decompressor to use.
Create the restore directory.
```
$ mkdir -p restore
```
Extract the .tar.xz archive into the restore directory.
```
$ tar --extract --verbose --file project-backup.tar.xz --directory=restore
project-backup/
project-backup/reports/
project-backup/reports/report.txt
project-backup/beta.log
project-backup/alpha.txt
```
Extracting into an existing directory can overwrite files that have the same archived paths and names. Listing the archive first and unpacking into an empty directory reduces that risk.
Compare the restored tree against the archive.
```
$ tar --compare --file project-backup.tar.xz --directory=restore
```
No output means the extracted files match the archived paths and contents. If tar prints a file path, inspect that restored file before using the extracted tree.