In Linux, the tr command is used to translate, squeeze, and/or delete characters. So with the help of the tr command, you can convert the case of any character. You can do this quickly with a single-line command. You can use the following command to convert a string to lowercase. Here the command takes the standard input of a string and processes it. Let’s discuss with an example.


Let’s create a sample shell script. Initialize a variable with a string having a few uppercase letters. Then convert all the letters to lowercase and store them in another variable.

Run the above script and see the results: You can see the result string has all the characters in lowercase.