Email-like text
Input
{"pattern":"[\\w.-]+@[\\w.-]+\\.\\w+","flags":"gi","text":"Contact [email protected] or [email protected]"}Output
[email protected], [email protected]
Regex Tester
Try a JavaScript regular expression against sample text and inspect matches, indexes, capture groups, and replacement output.
Developer tools
What it helps with
- Test a pattern against sample text
- Inspect capture groups
- Preview simple replacements before using them elsewhere
How to use
- Enter a JavaScript regular expression pattern and choose flags.
- Paste sample text and optionally add replacement text.
- Review matches, indexes, capture groups, highlights, and the replacement preview.
Examples
Capture key values
Input
{"pattern":"(?<key>\\w+)=(\\d+)","flags":"g","text":"id=42 count=7","replacement":"$1: $2"}Output
id=42, count=7
Good to know
- JavaScript regex syntax may differ from other languages.
- Some patterns can be slow in the browser.
- Shows the first 500 matches.
- This tool is for testing, not security validation.
FAQ
- Which regex syntax is used?
- This tool uses JavaScript regular expression syntax.
- What happens with invalid patterns?
- Syntax errors are shown as readable messages without crashing the page.
- Does this validate regex security?
- No. It is for interactive testing and debugging, not security validation.
Related tools
Nearby utilities from the KoguNavi toolbox.