Regex Tester & Debugger

Validate your Regular Expressions against test strings in real-time.

Pattern & Flags

Test String

Live Results

2 Matches Found

Contact us at [email protected] or [email protected] for help. Visit https://syntaxsnap.com for more tools. Server IP: 192.168.1.1 connected on 2025-10-25.

Capture Groups

#	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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Next step

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Need this built into your stack?

The team behind SyntaxSnap builds custom code generators, internal developer tools and API integrations.

Chrome extension