Regex Tester
Featured
Test regular expressions against sample text.
- On your device
- No signup
Private on your device
Your information stays on your device and is not uploaded.
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Test JavaScript regular expressions against sample text with highlighted matches, capture details, and token-by-token explanations. Runs locally in your browser.
How to use this tool
Open the Regex Debugger form on this page, enter the values or file required for your task, and run the tool. Review the results panel and adjust inputs as needed. Your data stays on your device and is not uploaded.
How it works
Enter a regular expression and sample text to debug matches, capture groups, highlighted output, and token-by-token explanations. Everything runs locally in your browser.
Limitations
Results are based on the inputs you provide and may not cover every edge case. This tool is for general use and is not professional advice.
Privacy and file handling
Your data stays on your device and is not uploaded.
FAQ
Frequently asked questions
Is Regex Debugger free?
Yes. It is free to use and you do not need to sign in or create an account.
Is my data private?
See the privacy note on this page. Many tools run on your device; some heavier file tools may use secure temporary processing when required.
Can I use Regex Debugger on mobile?
Yes. Open this page on your phone or tablet, enter your inputs, and use the on-screen controls.
Related pages
- Browse all free online tools on Utilnivo
- Explore more developer tools on Utilnivo
- Regex Tester — Test regular expressions against sample text.
- Regex Cheat Sheet Generator — Build a printable regex cheat sheet for patterns you need.
- Text Difference Checker — Compare two pieces of text and highlight changes.
- JSON Formatter — Format, minify, and validate JSON with optional key sorting.
- Character Counter — Count characters with and without spaces in real time.
- JSON Compare — Compare two JSON documents and list structural differences.
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