Regex Tester & Debugger
Validate your Regular Expressions against test strings in real-time.
Pattern & Flags
| # | Match | Index | Groups |
|---|---|---|---|
| 1 | [email protected] | 14 | - |
| 2 | [email protected] | 40 | - |
Why use this tester?
Regular Expressions can be tricky. This tool provides a safe, sandboxed environment to test your patterns against various strings without needing to run a server or console.
Frequently Asked Questions
Which Regex engine does this tester use?
This tool uses your browser's native ECMAScript Regular Expression engine. This ensures 100% accuracy for JavaScript and TypeScript development.
Are my test strings saved?
No. SyntaxSnap is a local-first platform. All testing happens in your browser's memory and is cleared when you refresh the page.
How do I use flags?
You can add flags like 'g' (global) or 'i' (insensitive) directly in the pattern input to control how the regex engine matches your text.
Does this tool protect against ReDoS attacks?
Yes. Our tester includes a built-in circuit breaker that stops execution if a pattern is too complex (catastrophic backtracking), preventing your browser from freezing.
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