Question 1

What is a regular expression (Regex)?

Accepted Answer

A regular expression (Regex) is a sequence of characters used to search, match and manipulate text based on specific patterns.

Question 2

Which regex engine does this tool use?

Accepted Answer

This tool uses the native JavaScript RegExp engine, making it ideal for testing patterns used in JavaScript, TypeScript and modern web applications.

Question 3

What do regex flags mean?

Accepted Answer

Regex flags modify how a pattern behaves. For example, 'g' performs a global search, 'i' ignores letter case, 'm' enables multiline matching, 's' allows dot to match newlines, 'u' enables Unicode support and 'y' enables sticky matching.

Question 4

Is this Regex Tester secure?

Accepted Answer

Yes. All regular expression matching is performed locally in your browser. No text or patterns are uploaded to any server.

Question 5

Can I test complex regular expressions?

Accepted Answer

Yes. You can test simple or advanced regular expressions including capturing groups, lookaheads, lookbehinds and Unicode patterns supported by your browser.

Regex Tester

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