Regex Tester
Test JavaScript regular expressions and inspect match indexes in your browser.
Regex tester
Test JavaScript regular expressions and inspect matches locally.
1 matches
- tool at index 24
Free regex tester
Use this tool to test search patterns for validation, log parsing, text cleanup, or JavaScript development.
How to Use Regex Tester (Step-by-Step)
Enter a regex pattern and flags.
Paste the text you want to test.
Review each match and its index.
Applications
Common Use Cases
- Test validation patterns before using them in code.
- Debug log parsing, text extraction, or cleanup expressions.
- Check JavaScript regex flags and match counts.
Privacy Guarantee
Zero Server Uploads
Unlike traditional online converters that upload your confidential documents to external cloud servers, MultiToolX executes computations in your browser runtime via HTML5 Canvas, Web Crypto, and WebAssembly.
Your data never leaves your device and cannot be viewed, stored, or harvested by anyone.
JavaScript Regular Expressions (RegEx) Cheatsheet and Tester Guide
A complete guide to regular expressions in JavaScript. Test regex patterns against text with live visual match highlighting and group capture.
FAQ
Frequently Asked Questions
Which regex flavor does this use?
It uses JavaScript regular expressions through the browser RegExp API.
Why does my regex error?
The pattern or flags may be invalid for JavaScript regular expressions.
Is my test text uploaded?
No. Matching runs locally in your browser.
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