What do the flags do?

"g" finds all matches instead of stopping at the first one; "i" makes the match case-insensitive; "m" changes how ^ and $ behave across multiple lines.

What happens if my pattern is invalid?

The tool shows a clear error message describing the problem instead of crashing or silently failing.

Regex Tester

Test a regular expression against sample text and see every match.

PatternFlags

Test text

2 matches:

12345

Processing happens locally in your browser. Nothing you enter is uploaded.

How It Works

Enter a pattern, optional flags (like g or i), and test text. Matches update instantly, and invalid patterns show a clear error.

Example

The pattern \d+ against "Order #12, order #345" matches "12" and "345".

Frequently Asked Questions

What do the flags do?: "g" finds all matches instead of stopping at the first one; "i" makes the match case-insensitive; "m" changes how ^ and $ behave across multiple lines.
What happens if my pattern is invalid?: The tool shows a clear error message describing the problem instead of crashing or silently failing.

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