`gzip` Compress and decompress files

Shrinks a single file using the gzip format, which adds a .gz ending. It does not bundle several files together, so use tar first when you need that. gunzip, or gzip -d, undoes the compression.

Synopsis

gzip [OPTION]... [FILE]...
gzip -d [OPTION]... [FILE.gz]...

Common options

Option or form	What it does
`-k, --keep`	Keep the original file. Without it, gzip deletes the input once it has made the .gz
`-d, --decompress`	Decompress instead of compress. Same as running gunzip
`-c, --stdout`	Write the result to standard output and leave the original file untouched
`-l, --list`	Show compressed size, uncompressed size and ratio for .gz files
`-t, --test`	Check that a .gz file is intact
`-v, --verbose`	Show the name and compression ratio for each file
`-1 to -9`	Compression level. -1 (--fast) is quickest, -9 (--best) is smallest but slowest. The default is 6
`-r, --recursive`	Compress every file inside folders you name, one by one

Examples

Compress a file and keep the original

gzip -k app.log && ls app.log*

app.log
app.log.gz

Compress to a new file with the original left alone

gzip -c notes.txt > notes.txt.gz && ls notes.txt*

notes.txt
notes.txt.gz

Read a compressed file without unpacking it

gzip -k words.txt && gzip -dc words.txt.gz | sort -u

apple
fig
pear

Check a .gz file is not damaged

gzip -k data.csv && gzip -t data.csv.gz

Compress at maximum level

gzip -9 -k data.csv && ls data.csv*

data.csv
data.csv.gz

Replace a file by its compressed copy, then restore it

gzip app.log && ls app.log* && gzip -d app.log.gz && ls app.log*

app.log.gz
app.log

Notes

By default gzip removes the original file after compressing it, and gzip -d removes the .gz file after decompressing. Use -k to keep it. -k exists in the gzip that ships with macOS. Very old gzip versions on other systems may not have it, so use -c with a redirect there.
gzip works on one file at a time. To compress a folder, make a tar archive and compress that, for example tar -czf backup.tgz docs.
gzip will skip a file if the result already exists, with a message such as "already exists -- skipping". Remove or rename the old file, or use -f to overwrite it.
Compressed text shrinks a lot, but photos, videos and zip files are already compressed and gain little or nothing.

gzip Compress and decompress files

Synopsis

Common options

Examples

Notes

See also

`gzip` Compress and decompress files