Regex Tester
Test JavaScript regular expressions with match positions and capture groups in a timeout-protected Web Worker.
🔒 Inputs and generated values are processed in the browser; text, QR content, passwords and participant lists themselves are not stored on the server.
🧾 How to use
1. Enter the text or values required for Regex Tester.
2. Choose the available options.
3. Review the live result or run the tool.
4. Copy or download the result when available.
Test JavaScript regular expressions with match positions and capture groups in a timeout-protected Web Worker.
2. Choose the available options.
3. Review the live result or run the tool.
4. Copy or download the result when available.
Test JavaScript regular expressions with match positions and capture groups in a timeout-protected Web Worker.
ⓘ Option guide / important notes
Regular expression note
- This tool uses JavaScript regular-expression syntax. Extremely expensive patterns may be terminated after a timeout to keep the browser responsive.
- In regex find/replace, JavaScript replacement syntax such as $1 and $2 can reference capture groups.
💡 Useful for
Useful for repetitive Regex Tester work during writing, development and data cleanup without installing software.
⚠ Notes
Very large text can consume significant browser memory/CPU, so recommended sizes and hard limits are enforced.
❔ Frequently Asked Questions
How do I use Regex Tester?
Test JavaScript regular expressions with match positions and capture groups in a timeout-protected Web Worker.
Is my input stored on the server?
No. Only aggregate run/success/failure/download counts are recorded; actual text, QR content, passwords and participant values are not stored.
What should I check before using the result?
Inputs and results are processed locally in the browser whenever supported.