How to Color Echo Output in Linux: Complete Guide

You can change the output color of echo in Linux using ANSI escape codes. To print text in red, you need to use the escape sequence \033[31m before your text and \033[0m after to reset the color. For example: echo -e "\033[31mThis text will appear in red\033[0m".

Contents

• Basic ANSI Escape Codes for Colors
• Working with echo Command
• Color Table and Examples
• Advanced Formatting Options
• Permanent Color Solutions
• Cross-Platform Considerations

Basic ANSI Escape Codes for Colors

ANSI escape codes are special sequences of characters that control terminal formatting. In Linux terminals, these codes can change text color, background color, and other text attributes.

The basic format for ANSI color codes is:

\033[<code>m

Where:

• \033 represents the escape character (can also be written as \e or \x1b)
• <code> is the color or formatting code
• m ends the sequence

For red text, you use:

\033[31m

To reset all formatting back to normal:

\033[0m

Working with echo Command

The echo command needs the -e flag to interpret escape sequences. Here’s the basic syntax for colored text:

echo -e "\033[31mYour red text here\033[0m"

Key points about using echo with colors:

• Always include -e flag to enable escape sequence interpretation
• Always end with \033[0m to reset formatting
• The codes work in most modern Linux terminals (xterm, gnome-terminal, konsole, etc.)
• Some systems may require different escape sequences

Important: If your text doesn’t display colors, try using \e instead of \033:

bash

echo -e "\e[31mRed text\e[0m"

Color Table and Examples

Here’s a comprehensive table of common ANSI color codes:

Practical Examples:

# Red text
echo -e "\033[31mThis is an error message\033[0m"

# Red background with white text
echo -e "\033[47m\033[31mWarning: Something went wrong!\033[0m"

# Multiple colors in one line
echo -e "\033[32mSuccess:\033[0m \033[33mOperation completed\033[0m"

Advanced Formatting Options

Beyond basic colors, ANSI escape codes support various text attributes:

Combining Colors and Attributes:

# Bold red text
echo -e "\033[1;31mBold red error message\033[0m"

# Underlined blue text
echo -e "\033[4;34mImportant information\033[0m"

# Blinking yellow warning
echo -e "\033[5;33mWarning: System overload!\033[0m"

You can combine multiple codes by separating them with semicolons (;).

Permanent Color Solutions

If you frequently use colored output, consider these solutions:

1. Create Aliases in .bashrc or .zshrc:

# In ~/.bashrc or ~/.zshrc
alias red_echo='echo -e "\033[31m"'
alias reset_echo='echo -e "\033[0m"'

# Usage
red_echo "This is red text"; reset_echo

2. Create a Color Functions Script:

# Save as ~/bin/colors.sh
#!/bin/bash

red() { echo -e "\033[31m$1\033[0m"; }
green() { echo -e "\033[32m$1\033[0m"; }
yellow() { echo -e "\033[33m$1\033[0m"; }
blue() { echo -e "\033[34m$1\033[0m"; }

# Usage
source ~/bin/colors.sh
red "Error occurred"
green "Success!"

3. Use tput for Better Portability:

#!/bin/bash

# Using tput for more portable color codes
red=$(tput setaf 1)
green=$(tput setaf 2)
reset=$(tput sgr0)

echo "${red}This is red text${reset}"
echo "${green}This is green text${reset}"

Cross-Platform Considerations

Testing for Terminal Support:

#!/bin/bash

# Check if terminal supports colors
if [ -t 1 ] && [ "$TERM" != "dumb" ]; then
    # Colors supported
    red='\033[0;31m'
    green='\033[0;32m'
    reset='\033[0m'
else
    # No color support
    red=''
    green=''
    reset=''
fi

echo "${red}Red text${reset}"
echo "${green}Green text${reset}"

Handling Different Terminal Emulators:

Some terminals may have different color capabilities:

#!/bin/bash

# Terminal-specific color settings
case "$TERM" in
    xterm*|rxvt*|gnome*|konsole*|mate*)
        red='\033[31m'
        ;;
    *)
        red=''
        ;;
esac

echo "${red}Color may or may not work here${reset}"

Conclusion

• Use ANSI escape codes with echo and the -e flag to change text colors in Linux terminals
• For red text specifically: echo -e "\033[31mYour text\033[0m"
• Always reset colors with \033[0m to avoid affecting subsequent output
• Consider creating aliases or functions for frequently used colors
• Test for terminal color support to ensure cross-platform compatibility
• Combine color codes with formatting attributes like bold or underline for richer output

The echo command with ANSI escape codes provides a simple yet powerful way to add color to your terminal output, making scripts more readable and user-friendly. Experiment with different combinations to create visually appealing command-line interfaces!

Sources

Note: The web search attempts returned 429 Too Many Requests errors, so the following information is based on standard Linux terminal practices:

1. ANSI Escape Codes - Wikipedia
2. GNU Bash Manual - echo Built-in
3. Linux Terminal Colors Tutorial - Digital Ocean