Linux grep and ripgrep Cheat Sheet

grep ERROR app.log

# Print lines containing a pattern.

grep -i timeout app.log

# Match regardless of uppercase or lowercase.

grep -n TODO src/app.js

# Display line numbers with matches.

grep -c ERROR app.log

# Only show the number of matches.

grep -v '^#' .env

# Print lines that do not match.

grep -w user auth.log

# Avoid partial substring matches.

grep -E 'warn|error|fatal' app.log

# Enable `+`, `?`, and alternation without heavy escaping.

grep -F 'a+b*c' notes.txt

# Disable regex interpretation.

grep '^ERROR.*timeout$' app.log

# Search with anchors.

grep -n '^$' file.txt

# Search for empty lines.

grep -n '[^[:space:]]' file.txt

# Show lines containing at least one non-space character.

grep -R 'TODO' src/

# Search all files under a directory.

grep -Rn 'TODO' src/

# Show file names and line numbers for matches.

grep -R --include='*.ts' 'useEffect' src/

# Restrict recursive search to certain extensions.

grep -R --exclude-dir=node_modules 'axios' .

# Skip noisy folders like node_modules or dist.

grep -Rl 'TODO' src/

# Show only files that contain a match.

grep -B 3 ERROR app.log

# Print 3 lines before each match.

grep -A 5 ERROR app.log

# Print 5 lines after each match.

grep -C 2 ERROR app.log

# Print context on both sides of a match.

rg TODO src/

# Fast codebase search.

rg -n 'useState' src/

# Show matches with file and line context.

rg -g '*.ts' 'useEffect' src/

# Restrict search by glob.

rg --hidden 'apiKey' .

# Search dotfiles and hidden paths.

rg -F 'http://localhost:3000' .

# Disable regex parsing for a search term.

rg -l 'TODO|FIXME' src/

# Return only matching file names.