Regex Tester
Test regular expressions with live matches, flags, and capture groups. It is fast, free, and designed for everyday development work.
🔒Private by design. Nothing is uploaded—this tool runs entirely in your browser.
How to use this tool
- Paste or type the content you want to process in the input area.
- Add the second input or options shown for this tool, when required.
- Select “Test expression” to process everything locally in your browser.
- Check the result carefully, then use the copy button to save it.
How Regex Tester works
Regular expressions describe text patterns for searching, validation, and extraction. Testing against representative input makes it easier to understand matches, capture groups, anchors, repetition, and edge cases.
The browser creates a native RegExp from the supplied pattern and applies it globally across the sample text. Each match is listed with any captured groups so you can inspect what the expression actually selected.
Regex behavior and supported features vary between JavaScript and other engines such as PCRE, Python, or .NET. Avoid catastrophic backtracking on untrusted input, and test both expected matches and values that must be rejected.
Frequently asked questions
What does Regex Tester do?
Test regular expressions with live matches, flags, and capture groups.
Is Regex Tester free?
Yes. You can use the complete tool without an account, subscription, or usage limit.
Is my input uploaded anywhere?
No. The tool processes your input inside the current browser tab and does not send editor content to a Toolsvanta processing server.
Does it work on mobile?
Yes. The input, controls, and results adapt to smaller screens, although larger code or data samples are usually easier to inspect on desktop.
Can I use the result in a commercial project?
Yes. You may use the result in personal or commercial work. Always review and test important output before deploying it.
Does Toolsvanta save my work?
No. Input and results are not saved by the tool. Copy anything you want to keep before closing or refreshing the page.
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