10 Practical Linux Cut Command Examples to Select File Columns

by Balakrishnan Mariyappan on June 6, 2013

Linux command cut is used for text processing. You can use this command to extract portion of text from a file by selecting columns.

This tutorial provides few practical examples of cut command that you can use in your day to day command line activities.

For most of the example, we’ll be using the following test file.

$ cat test.txt
cat command for file oriented operations.
cp command for copy files or directories.
ls command to list out files and directories with its attributes.

1. Select Column of Characters

To extract only a desired column from a file use -c option. The following example displays 2nd character from each line of a file test.txt

$ cut -c2 test.txt
a
p
s

As seen above, the characters a, p, s are the second character from each line of the test.txt file.

2. Select Column of Characters using Range

Range of characters can also be extracted from a file by specifying start and end position delimited with -. The following example extracts first 3 characters of each line from a file called test.txt

$ cut -c1-3 test.txt
cat
cp
ls

3. Select Column of Characters using either Start or End Position

Either start position or end position can be passed to cut command with -c option.

The following specifies only the start position before the ‘-’. This example extracts from 3rd character to end of each line from test.txt file.

$ cut -c3- test.txt
t command for file oriented operations.
 command for copy files or directories.
 command to list out files and directories with its attributes.

The following specifies only the end position after the ‘-’. This example extracts 8 characters from the beginning of each line from test.txt file.

$ cut -c-8 test.txt
cat comm
cp comma
ls comma

The entire line would get printed when you don’t specify a number before or after the ‘-’ as shown below.

$ cut -c- test.txt
cat command for file oriented operations.
cp command for copy files or directories.
ls command to list out files and directories with its attributes.

4. Select a Specific Field from a File

Instead of selecting x number of characters, if you like to extract a whole field, you can combine option -f and -d. The option -f specifies which field you want to extract, and the option -d specifies what is the field delimiter that is used in the input file.

The following example displays only first field of each lines from /etc/passwd file using the field delimiter : (colon). In this case, the 1st field is the username. The file

$ cut -d':' -f1 /etc/passwd
root
daemon
bin
sys
sync
games
bala

5. Select Multiple Fields from a File

You can also extract more than one fields from a file or stdout. Below example displays username and home directory of users who has the login shell as “/bin/bash”.

$ grep "/bin/bash" /etc/passwd | cut -d':' -f1,6
root:/root
bala:/home/bala

To display the range of fields specify start field and end field as shown below. In this example, we are selecting field 1 through 4, 6 and 7

$ grep "/bin/bash" /etc/passwd | cut -d':' -f1-4,6,7
root:x:0:0:/root:/bin/bash
bala:x:1000:1000:/home/bala:/bin/bash

6. Select Fields Only When a Line Contains the Delimiter

In our /etc/passwd example, if you pass a different delimiter other than : (colon), cut will just display the whole line.

In the following example, we’ve specified the delimiter as | (pipe), and cut command simply displays the whole line, even when it doesn’t find any line that has | (pipe) as delimiter.

$ grep "/bin/bash" /etc/passwd | cut -d'|'  -f1
root:x:0:0:root:/root:/bin/bash
bala:x:1000:1000:bala,,,:/home/bala:/bin/bash

But, it is possible to filter and display only the lines that contains the specified delimiter using -s option.

The following example doesn’t display any output, as the cut command didn’t find any lines that has | (pipe) as delimiter in the /etc/passwd file.

$ grep "/bin/bash" /etc/passwd | cut -d'|' -s -f1

7. Select All Fields Except the Specified Fields

In order to complement the selection field list use option –complement.

The following example displays all the fields from /etc/passwd file except field 7

$ grep "/bin/bash" /etc/passwd | cut -d':' --complement -s -f7
root:x:0:0:root:/root
bala:x:1000:1000:bala,,,:/home/bala

8. Change Output Delimiter for Display

By default the output delimiter is same as input delimiter that we specify in the cut -d option.

To change the output delimiter use the option –output-delimiter as shown below. In this example, the input delimiter is : (colon), but the output delimiter is # (hash).

$ grep "/bin/bash" /etc/passwd | cut -d':'  -s -f1,6,7 --output-delimiter='#'
root#/root#/bin/bash
bala#/home/bala#/bin/bash

9. Change Output Delimiter to Newline

In this example, each and every field of the cut command output is displayed in a separate line. We still used –output-delimiter, but the value is $’\n’ which indicates that we should add a newline as the output delimiter.

$ grep bala /etc/passwd | cut -d':' -f1,6,7 --output-delimiter=$'\n'
bala
/home/bala
/bin/bash

10. Combine Cut with Other Unix Command Output

The power of cut command can be realized when you combine it with the stdout of some other Unix command.

Once you master the basic usage of cut command that we’ve explained above, you can wisely use cut command to solve lot of your text manipulation requirements.

The following example indicates how you can extract only useful information from the ps command output. We also showed how we’ve filtered the output of ps command using grep and sed before the final output was given to cut command. Here, we’ve used cut option -d and -f which we’ve explained in the above examples.

$ ps axu | grep python | sed 's/\s\+/ /g' | cut -d' ' -f2,11-
2231 /usr/bin/python /usr/lib/unity-lens-video/unity-lens-video
2311 /usr/bin/python /usr/lib/unity-scope-video-remote/unity-scope-video-remote
2414 /usr/bin/python /usr/lib/ubuntuone-client/ubuntuone-syncdaemon
2463 /usr/bin/python /usr/lib/system-service/system-service-d
3274 grep --color=auto python

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{ 18 comments… read them below or add one }

1 Jalal Hajigholamali June 6, 2013 at 8:48 am

Hi,

simple and very nice and useful article

2 Bob June 6, 2013 at 9:41 am

Great article.

3 Srinivas Jupudi June 7, 2013 at 12:22 am

Nice Article

4 niraj June 7, 2013 at 12:28 am

Nice artical

5 Erlo June 7, 2013 at 1:07 pm

Linux/Unix has lots of nice little utilities :o ) I was not aware of cut, I have always used awk for these things. awk combined with sed is a kind of swiss pocket knife.

6 xlob June 7, 2013 at 8:01 pm

Thanks for article.
@Erlo For substitution awk can use gsub internal command instead of pipe into sed ?

7 ASHOK July 4, 2013 at 10:01 pm

I wish to extract specific data from a line
I mean
Input : OA.jsp?page=/hello/abc/123/a23/sam/store/web/helloworld&xyz=YES
Output: OA.jsp?page=/hello/abc/123/a23/sam/store/web/helloworld

& should act as delimiter. The length of the link may change.
What ever the link I pass the data before & should display.

How it is possible?

8 John Joseph September 4, 2013 at 1:11 am

Well written and it has been useful for me. Thank you.

9 Sandeep October 23, 2013 at 10:55 pm

Hi
Please can you do me favor. I need a script to get the information of all hosts running on network like.
Name =Home user
Disk usage space =
Disk Available space =
Disk Total space =
IP Address =

10 Nitin November 21, 2013 at 4:19 am

Dear Ashok,

You can use the below script for your required O/P:

cat input.txt | cut -d’&’ -f1

11 Amani Musomba February 19, 2014 at 11:39 am

One of the best articles I have found on the cut command..
Thanks for posting this..

12 sushil March 23, 2014 at 11:17 pm

With this command $ cut -c- test.txt
I am not getting any out.
Iam using fedora 19

13 Deiveegaraja March 31, 2014 at 5:48 am

Thanks..

14 Maniraja May 9, 2014 at 11:51 pm

Hi Sushil,

we need to mention the range while using cut with -c option.
like cut -c 1,5 test.txt.and cut -c 5- test.txt.

In the first e.g it will print the first five characters of each line.
In the second one, it will print the characters from 5 to the end of the line of each line.

15 Deepak Jadli October 27, 2014 at 5:49 am

It’s a proper and perfect docs :)
Thanks

16 Devi Killada October 28, 2014 at 11:53 am

Just now I was trying to google the practical examples of cut, got your blog. Revised all commands at once. Thanks for posting Bala.

17 tony November 5, 2014 at 5:18 pm

I have a little problem how would i solve this? its an assignment for school

Your current directory is sample_dir. Display cars2 sorted numerically by the 4th field:

i understand i need to use the cut command just don’t know how

18 saurabh November 10, 2014 at 8:52 am

Simple and effective article.

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