Regex Tester & Debugger
Test regex patterns with flags (`g`, `i`, `m`, `s`), view live highlighted matches, inspect capture groups, and diagnose syntax errors instantly.
How to use Regex Tester & Debugger
- 1Enter your regex pattern in the top field (without delimiters).
- 2Select active flags (g: global, i: ignore case, m: multiline, s: dotAll).
- 3Type or paste your test text in the box below.
- 4Review matching spans highlighted in yellow and the detailed capture group table.
Key Features & Capabilities
Frequently Asked Questions
What is the "g" (global) flag for?
The global flag instructs the regex engine to locate all matching instances in the string, rather than stopping after the first match.
Privacy & Security Commitment
Regex matching executes purely inside your local browser engine.
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