Grep Pattern Tester

Grep Pattern Tester

Filter and search text using exact strings or regular expressions, just like the Unix grep command — but with a visual interface.

Features

  • Exact String Mode — Match literal text with position options: contains, prefix, suffix, or exact match
  • Regex Mode — Full JavaScript regular expression support with flags (g, m, s, u, i)
  • Case Insensitive — Toggle case-insensitive matching
  • Whole Word — Match only complete words, not substrings
  • Invert Match — Show non-matching lines (like grep -v)
  • Context Lines — Show N lines before/after each match (like grep -B / grep -A)
  • Match Highlighting — Visual highlighting of matched text within results
  • Max Hits — Limit the number of results
  • Trim Whitespace — Strip leading/trailing whitespace from lines

Privacy

All processing happens entirely in your browser. Your text and patterns are never sent to any server.

Read the full Grep Pattern Tester guide and the Grep Pattern Tester API reference.