What is a regular expression (regex)?

A regular expression (regex) is a sequence of characters that defines a search pattern, commonly used for string matching and text processing. Learn more: - [Wikipedia – Regular expression](https://en.wikipedia.org/wiki/Regular_expression) - [MDN – Regular expressions](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Regular_expressions)

What does a regex tester do?

A regex tester allows you to test and debug regular expressions by showing which parts of the text match a given pattern in real time.

What regex flags are commonly supported?

Common regex flags include `g` (global), `i` (case-insensitive), and `m` (multiline). These flags modify how the regex engine processes matches.

Why should I use a regex tester?

Regex testers help you quickly verify patterns, debug matching issues, and learn how regular expressions behave with different inputs.

Is this regex tester language-specific?

This tool follows JavaScript-style regular expressions, which are widely used in web development.

Is my text sent to a server?

No. All regex testing is performed locally in your browser. No data is uploaded or stored.

FlowTooly

Regex Tester

Test and debug regular expressions instantly in your browser. Supports flags, match highlighting, and live results for easier regex development.

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