ToolHub

Online Regex Tester & Debugger

Test and debug JavaScript regular expressions online with live pattern matching, flag toggles, and regex breakdown cheatsheet.

100% Client-Side Privacy (No Upload)
//gi
Matches (0)
No regex matches found in test string.

How to Use Regex Tester & Debugger

  1. 1Type your regular expression pattern in the expression field.
  2. 2Toggle flags (Global `g`, Case Insensitive `i`, Multiline `m`).
  3. 3Paste test strings into the text body.
  4. 4View instant highlighted matches and capture groups.

Key Features

  • Real-time regex evaluation with visual match highlight badges.
  • Supports flags: `g`, `i`, `m`, `s`, `u`.
  • Detailed capture group output panel.

Frequently Asked Questions (FAQ)

ToolHub uses the native browser JavaScript RegExp engine for 100% fidelity.

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