Regex Tester
Data is processed securely within your browser.
Enter pattern and test string to view matches
What is a Regex Tester?
A Regex Tester is an online developer tool that allows you to instantly validate whether your Regular Expression matches a specific target string. It helps easily test patterns for email validation, phone number extraction, and more. ToolVill's Regex Tester operates entirely on the client-side, ensuring that your test text is never transmitted to an external server.
Key Features
- Real-time Match Validation: See matches and capture groups as you type your pattern or test string.
- Ready-to-use Presets: Insert common regex patterns like Email, Phone, and URL with a single click.
- Easy Flag Toggles: Turn g, i, and m flags on and off instantly to test different matching scenarios.
- 100% Private: Processed entirely within your browser for complete data privacy.
When Should You Use It?
- When checking if an email or password regex pattern works correctly for sign-up forms
- When extracting specific formats like phone numbers or error codes from long logs or text
- When validating the effect of flags like g (global) or i (case insensitive) instantly
Frequently Asked Questions (FAQ)
Which Regex engine is used?
This tool relies on the built-in JavaScript Regular Expression engine provided by your modern web browser.
Is my test data sent to a server?
No. In line with ToolVill's core principles, the Regex Tester runs strictly in your browser. Sensitive logs or data are entirely safe and are never transmitted externally.
What happens if I type an invalid regex?
If you input a regex with syntax errors, the tool securely catches the error and displays an 'Invalid Regular Expression' status without crashing the page.