Renaming multiple files and directories with the mv command can be a tedious process as it involves writing complex commands with pipes, loops, and so on.

This is where the rename command comes handy. It renames the given files by replacing the search  expression in their name with the specified replacement.

In this tutorial, we will explain how to use the rename command to batch rename files.

Installing rename

There are two versions of the rename command with different syntax and features. We will be using the Perl version of the rename command.

If this version is not installed on your system, use the package manager of your Linux distribution to install it:

Ubuntu and Debian

sudo apt update

CentOS and Fedora

sudo yum install prename

Arch Linux

yay perl-rename

Using rename

The following is the general syntax for the rename command:

rename [OPTIONS] perlexpr files

The rename command is basically a Perl script. It will rename the given files according to the specified perlexpr regular expression. You can read about Perl regular expressions here.

For example, the following command will change the extension of all .css files to .scss:

rename 's/.css/.scss/' *.css

Let’s explain the command in more details:

  • s/search_pattern/replacement/ - The substitution operator.
  • .css - The search pattern. It is the first argument in the substitution operator. The rename command will search for this pattern in the given file name and if found it will replace it with the replacement argument.
  • .scss - The replacement. The second argument in the substitution operator.
  • *.css - All files with “.css” extension. Wildcard (*) is a symbol used to represent zero, one or more characters.

Before running the actual command and rename the files and directories it is always a good idea to use the -n option that will perform a “dry run” and show you what files will be renamed:

rename -n 's/.css/.scss/' *.css

The output will look something like this:

rename(file-0.css, file-0.scss)
rename(file-1.css, file-1.scss)
rename(file-2.css, file-2.scss)
rename(file-3.css, file-3.scss)
rename(file-4.css, file-4.scss)

By default, the rename command doesn’t overwrite the existing files. Use the -f option which tells rename to overwrite the existing files:

rename -f 's/.css/.scss/' *.css

If you want rename to print the names of files that are successfully renamed, use the -v (verbose) option:

rename -v 's/.css/.scss/' *.css
file-0.css renamed as file-0.scss
file-1.css renamed as file-1.scss
file-2.css renamed as file-2.scss
file-3.css renamed as file-3.scss
file-4.css renamed as file-4.scss

rename Examples

Below are a few common examples of how to use the rename command:

Replace spaces in filenames with underscores

rename 'y/ /_/' *

Convert filenames to lowercase

rename 'y/A-Z/a-z/' *

Convert filenames to uppercase

rename 'y/a-z/A-Z/' *

Remove .bak from the filenames

rename 's/\.bak$//' *.bak

Rename .jpeg and .JPG filenames to .jpg

rename 's/\.jpe?g$/.jpg/i' *


The rename command allows you to rename multiple files at once, using Perl regular expressions.

If you have any questions or feedback, feel free to leave a comment.