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Regex Tester & Regular Expression Debugger

Test, debug, and validate JavaScript regular expressions in real-time with instant match highlighting, capture group extraction, and regex cheat sheet.

Presets:
//gi
Pattern compiled successfully2 matches found
Match ResultsCount: 2
Match #1index 19
help@thechoicervoicergame.online
Match #2index 55
dev-team@choicervoicer.com

How to Use the Regex Tester & Regular Expression Debugger

  1. 1Enter your regular expression pattern and toggle flags (Global `g`, Case-Insensitive `i`, Multiline `m`, DotAll `s`).
  2. 2Type or paste your test text in the test string area.
  3. 3Inspect real-time color-coded match highlights, match count, start/end indices, and capture groups.

Key Features & Capabilities

  • Real-time syntax highlighting for matches and numbered capture groups
  • Regex substitution / replace preview tool
  • Built-in quick templates: Email, URL, Phone Number, Date, IP Address, Hex Color, Strong Password
  • Comprehensive cheat sheet for anchors, character classes, quantifiers, and lookaheads

Frequently Asked Questions

What is the difference between the `g` and `i` flags in Regex?

The `g` (global) flag ensures the engine finds all matches in the text rather than stopping after the first match. The `i` (case-insensitive) flag causes matching to treat lowercase and uppercase letters as equal.

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