Regex Tester
Developer ToolsTest and debug regular expressions in real-time. See matches highlighted, capture groups, and get explanations for your patterns.
Regex Tester — Test and debug regular expressions in real-time. See matches highlighted, capture groups, and get explanations for your patterns. All processing happens instantly in your browser with zero data sent to any server.
Step-by-Step Guide
- 1Enter your data into the input area at the top of the tool.
- 2Configure any options or settings as needed.
- 3Click the primary action button to process your data.
- 4Copy the result using the Copy button, or download if available.
- 5Use Clear/Reset to start over with new data.
Use Cases
- •Quick developer tasks without installing software
- •Processing sensitive data securely in your browser
- •Batch processing when working on multiple projects
- •Learning and experimenting with developer concepts
Pro Tips
- 💡All data stays in your browser — safe for confidential content.
- 💡Bookmark this page for quick access from your browser toolbar.
- 💡Check the Related Tools section below for complementary utilities.
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Frequently Asked Questions
A Regex Tester lets you write regular expression patterns and test them against sample text in real-time, showing all matches and capture groups.
Enter your regex pattern, set flags (g, i, m), type your test string, and see matches highlighted in real-time.
Yes, completely free with no registration.
All regex processing happens in your browser. No data is sent anywhere.
The tool uses JavaScript's built-in RegExp engine, which supports most common regex features including lookahead, lookbehind, and named groups.
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