Question 1

What is a regular expression (regex)?

Accepted Answer

A regular expression is a sequence of characters that defines a search pattern. It's used for pattern matching within strings, making it powerful for text processing, validation, and search operations.

Question 2

What regex flags does this tester support?

Accepted Answer

This regex tester supports all standard JavaScript regex flags: g (global), i (case-insensitive), m (multiline), s (dotAll), u (unicode), and y (sticky).

Question 3

How do I use capture groups in regex?

Accepted Answer

Capture groups are created using parentheses (). For example, (\w+) captures one or more word characters. You can reference captured groups in replacements using $1, $2, etc.

Question 4

What makes this regex tester different from others?

Accepted Answer

This regex tester provides live syntax highlighting, shows capture groups clearly, offers real-time match visualization, and includes replacement preview functionality. It's completely free with no uploads required.

Question 5

Can I test complex regex patterns?

Accepted Answer

Yes, you can test any valid JavaScript regular expression, including complex patterns with lookaheads, lookbehinds, backreferences, and advanced quantifiers.

Regex Tester

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