The echo Command in Linux: Print Text and Variables with Examples

Applies to: Bash 5.2.37 and GNU coreutils 9.7 on Debian 13 (tested); the same on other Linux distributions with Bash

echo prints its arguments followed by a new line. The $ belongs to the shell, not to echo: before echo runs, Bash replaces $name with the value of the variable name. So echo $HOME prints your home folder.

Print text and variables

$ name="Ucartz"
$ echo "Hello $name"
Hello Ucartz
$ echo "Home: $HOME, user: $USER, shell: $SHELL"
Home: /root, user: root, shell: /bin/bash
$ echo "Path is: $PATH"
Path is: /usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin

Use braces when letters follow the variable name. Without them, Bash looks for a different variable:

$ echo "Hello ${name}s"
Hello Ucartzs
$ echo "Hello $names."
Hello .

An unset variable prints as nothing, without an error. To show a fallback instead: echo "${UNSET_VAR:-default value}" printed default value.

Double quotes, single quotes and no quotes

$ echo "Hello $name"
Hello Ucartz
$ echo 'Hello $name'
Hello $name
$ echo "Cost: \$5"
Cost: $5

Double quotes replace variables; single quotes print everything exactly as typed. Without quotes, Bash also splits the value on spaces and expands wildcards:

$ files="a   b"
$ echo $files
a b
$ echo "$files"
a   b
$ echo *
app.log index.html style.css
$ echo "*"
*

So put variables in double quotes unless you have a reason not to.

Special $ variables

• $?: exit status of the last command. false; echo $? printed 1, true; echo $? printed 0.
• $$: process ID of the current shell.
• $0: name of the script, for example /echo.sh in our test.
• $1, $2, $#, $@: script arguments, their number and all of them. After set -- one two three, echo "args: $# first: $1 all: $@" printed args: 3 first: one all: one two three.

Command output and arithmetic

$ echo "Today is $(date +%A)"
Today is Tuesday
$ echo "2 + 3 = $((2 + 3))"
2 + 3 = 5

$( ) runs a command and inserts its output; $(( )) does whole-number arithmetic.

Options: -n and -e

$ echo -n "no newline"; echo "|"
no newline|
$ echo "line1\nline2"
line1\nline2
$ echo -e "line1\nline2"
line1
line2
$ echo -e "col1\tcol2"
col1	col2

-n leaves out the final new line; -e turns on escapes such as \n (new line) and \t (tab).

Scripts that start with #!/bin/sh behave differently on Debian and Ubuntu, where /bin/sh is dash. There, echo "line1\nline2" printed two lines, and echo -e "x\ty" printed -e x y. Use #!/bin/bash or printf if the output must be the same everywhere.

Write to a file

echo "hello" > /tmp/out.txt     # replace the file
echo "again" >> /tmp/out.txt    # add a line at the end

sudo echo "text" > /etc/file fails with -bash: /etc/file: Permission denied, because your own shell opens the file, not sudo. Use tee instead:

echo "nameserver 1.1.1.1" | sudo tee -a /etc/test.conf

When to use printf instead

echo can’t print a value that looks like one of its options: echo "-n" printed nothing at all. printf prints any value safely and gives you control over the format:

$ printf '%s\n' "-n"
-n

In Bash, echo is a shell builtin (type echo says echo is a shell builtin). There is also a separate program, /bin/echo, from GNU coreutils.

Related: set environment variables, set $PATH permanently, a script with variables and redirect standard error.

Official documentation: Bash reference manual, builtin commands.