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cut Command in Linux: Extract Fields, Bytes & Practical Examples

cut prints selected bytes, characters, or delimiter-separated fields from each line of a file or pipeline. It is the fast first choice for usernames from /etc/passwd, CSV columns, and fixed-width snippets in shell scripts.

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Reviewed byDeepak Prasad

cut Command in Linux: Extract Fields, Bytes & Practical Examples
About cut prints selected bytes, characters, or delimiter-separated fields from each line of a file or pipeline. It is the fast first choice for usernames from /etc/passwd, CSV columns, and fixed-width snippets in shell scripts.
Tested on Ubuntu 25.04 (Plucky Puffin); cut (uutils coreutils) 0.2.2; kernel 7.0.0-27-generic
Package coreutils-from-uutils (apt/deb) · coreutils (dnf/rpm)
Man page cut(1)
Privilege none
Distros

GNU coreutils and uutils coreutils (Ubuntu 25.04 ships uutils cut).

Variable-width space columns: awk is often more reliable than a single-space delimiter.

cut — quick reference

Field mode

Extract columns separated by a delimiter — default is tab; colon is common in /etc/passwd.

When to use Command
First field with default tab delimiter cut -f 1 file
First field with colon delimiter cut -d ':' -f 1 /etc/passwd
Multiple fields (non-contiguous) cut -d ':' -f 1,3 /etc/passwd
Range of fields cut -d ':' -f 1-3 /etc/passwd
From field N to end of line cut -d ':' -f 3- /etc/passwd
Only lines that contain the delimiter cut -d ':' -f 1 -s file
Split on any run of spaces/tabs (uutils -w) cut -w -f 1,3 file

Character and byte mode

Fixed-position extraction when data is not delimiter-separated.

When to use Command
Characters 1 through 5 on each line cut -c 1-5 file
Bytes 1 through 10 on each line cut -b 1-10 file
From character 5 to end cut -c 5- file
From start through character 10 cut -c -10 file
Non-contiguous character positions cut -c 1-5,10-15 file

Output control

When to use Command
Print everything except selected fields cut --complement -d ':' -f 2 file
Replace output delimiter (e.g. tab → space) cut -d ':' -f 1,3 --output-delimiter=' ' /etc/passwd
NUL-terminated records cut -z -f 1 file

Pipelines and metadata

When to use Command
Extract from command output ps aux | cut -c 1-20
Chain with grep ps aux | grep root | cut -c 1-30
Show built-in usage cut --help
Show package version cut --version

cut — command syntax

Synopsis from cut --help on Ubuntu 25.04 (uutils cut 0.2.2):

text 
cut OPTION... [FILE]...

Each invocation must pick a mode (-b, -c, or -f) and a list of positions or fields. With no FILE, cut reads stdin. Delimiter for -f defaults to tab unless -d or -w is set.

cut — command examples

Essential Extract usernames from /etc/passwd

The classic field cut: colon-separated fields, keep field 1.

Run the command:

bash 
cut -d ':' -f 1 /etc/passwd | head -3

Sample output:

text 
root
daemon
bin

Field 1 is the login name. Field 3 is UID, field 6 is home directory — same delimiter throughout the file.

Essential Select several fields from one line

Comma-separated field numbers print in the order you list them.

Run the command:

bash 
cut -d ':' -f 1,3 /etc/passwd | head -2

Sample output:

text 
root:0
daemon:1

Here you get username and UID without the password placeholder in field 2.

Essential From field 3 to end of line

A trailing hyphen means "through the last field" — useful when trailing fields vary in count.

Run the command:

bash 
cut -d ':' -f 3- /etc/passwd | head -2

Sample output:

text 
0:0:root:/root:/bin/bash
1:1:daemon:/usr/sbin:/usr/sbin/nologin

Everything from UID onward is kept. Pair with --output-delimiter when you need spaces instead of colons in the result.

Common Invert selection with --complement

Print all fields except the ones you name — handy to drop a middle column.

Run the command:

bash 
cut --complement -d ':' -f 2 /etc/passwd | head -2

Sample output:

text 
root:0:0:root:/root:/bin/bash
daemon:1:1:daemon:/usr/sbin:/usr/sbin/nologin

Field 2 (the x password placeholder) is removed; other colons stay.

Common -s skips lines without the delimiter

By default, cut prints whole lines that lack the delimiter. -s suppresses them — useful on messy logs.

Run the command:

bash 
cut -d ':' -f 1 -s /etc/shadow | head -3

Sample output (requires read access to /etc/shadow):

text 
root
daemon
bin

Only lines containing : are printed. On files where some lines are free text, -s keeps output clean.

Common Change the separator in output

--output-delimiter replaces the field separator in the printed columns.

Run the command:

bash 
cut -d ':' -f 1,3 --output-delimiter=' ' /etc/passwd | head -2

Sample output:

text 
root 0
daemon 1

Downstream tools that dislike colons (or tabs) can consume space-separated values directly.

Common Fixed character positions with -c

When columns are defined by width, not delimiters, use character mode.

Run the command:

bash 
printf 'abcdef\nghijkl\n' > /tmp/cut.txt
cut -c 1-3 /tmp/cut.txt

Sample output:

text 
abc
ghi

-b selects bytes (same result on ASCII); -c counts Unicode characters, which matters for multibyte text.

Common Trim wide command output in a pipeline

cut fits between filters when you only need the leftmost part of aligned output.

Run the command:

Find the blocking PID with ps aux piped to grep; the ps command explains BSD versus UNIX options and filtering command lines.

bash 
ps aux | head -3 | cut -c 1-20

Sample output:

text 
USER         PID %CP
root           1  0.
root           2  0.

For delimiter-separated command output (e.g. df), prefer -f with the right -d — or awk when spaces vary in width.

Advanced Whitespace-separated fields with -w (uutils)

On Ubuntu 25.04's uutils cut, -w treats any run of spaces or tabs as one separator — closer to how humans read columns.

Run the command:

bash 
printf 'one two  three\n' | cut -w -f 1,3

Sample output:

text 
one	three

Output delimiter defaults to tab unless you set --output-delimiter. GNU coreutils on other distros may not ship -w — check cut --help on the target host.

cut — when to use / when not

Use cut when Use something else when
  • Columns are separated by a single-character delimiter (tab, colon, comma)
  • You need one or more field numbers quickly in a shell pipeline
  • Data uses fixed character or byte positions
  • You want complement, output delimiter, or serialize-style field drops without a full language
  • Columns are separated by variable spaces → awk or cut -w where available
  • You need conditional logic, calculations, or pattern matching → awk
  • You need to merge parallel files into wider rows → paste
  • You need in-place editing → sed

cut vs awk

cut awk
Learning curve Small — one delimiter, field list Larger — patterns and expressions
Delimiter Single character (-d) or -w whitespace Any pattern in FS
Logic No conditionals Filters, math, keyed joins
Speed on huge files Very fast, minimal Fast, more flexible

Use cut for simple column pulls; reach for awk when rules get conditional.

Command One line
cut Extract bytes, chars, or fields (this page)
grep Filter lines before or after cutting

Browse the full index in our Linux commands reference.

cut — interview corner

What is the cut command used for?

cut prints selected bytes (-b), characters (-c), or fields (-f) from each input line. It is built for simple column extraction in scripts.

bash 
cut -d ':' -f 1 /etc/passwd

A strong answer is:

"cut extracts fixed positions or delimiter-separated fields from each line — I use it for passwd columns and quick pipeline trimming."

What is the default field delimiter in cut?

The default is tab. For colon files like /etc/passwd, set -d ':'.

Lines without the delimiter are printed whole unless you add -s (suppress).

A strong answer is:

"Tab by default; I set -d for colons or commas. -s drops lines that lack the delimiter."

When would you use awk instead of cut?

Use awk when delimiters are irregular (multiple spaces), you need conditions ($3 > 100), or you are matching patterns. cut wins when the format is stable and the task is "give me fields 1 and 3."

A strong answer is:

"awk for variable spacing, conditions, and patterns; cut for simple single-character delimiters and fixed field lists."

What does cut --complement do?

It inverts the field list — you get every field except the ones you named.

bash 
cut --complement -d ':' -f 2 /etc/passwd

drops field 2 (the x password token) and keeps the rest.

A strong answer is:

"--complement prints all fields except those listed — useful to drop one column without renumbering the ones you want."

How do you specify a range of fields in cut?

Use N-M for inclusive range, N- from N to end, -M from start to M. Combine with commas: -f 1,3-5.

bash 
cut -d ':' -f 1-3 /etc/passwd

A strong answer is:

"Ranges use hyphens — 1-3 or 3- for rest of line; commas combine multiple selections."

Troubleshooting

Symptom Likely cause Fix
Whole lines printed when you expected one field Line has no delimiter; -s not set Add -s or fix delimiter with -d
Empty columns with -d ' ' Multiple spaces count as multiple delimiters (without -w) Use cut -w on uutils or switch to awk
cut: you must specify a list of bytes, characters, or fields Missing -f, -c, or -b Add mode and list, e.g. -f 1
Wrong characters on UTF-8 text Byte vs character mode Prefer -c for characters, -b for raw bytes
--complement not recognized Very old coreutils Upgrade or select fields positively without complement
Rohan Timalsina

is a technical writer and Linux enthusiast who writes practical guides on Linux commands and system administration. He focuses on simplifying complex topics through clear explanations.