Developer Tools

Regex Tester – Free Online Tool

Test and debug regular expressions with live match highlighting, flags, and group captures.

How to Use Regex Tester

  1. Enter your regular expression pattern and flags (g, i, m, s).
  2. Paste your test string in the target area.
  3. See live highlights of every match and extracted capture groups.
  4. Inspect match indices and copy output.

Key Highlights & Features

  • ✓ Real-time match highlighting
  • ✓ Group captures breakdown
  • ✓ Common regex presets (email, URL, phone, IP)

Frequently Asked Questions

Which flags are supported?

Global (g), Case-insensitive (i), Multiline (m), DotAll (s), and Unicode (u).

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