How do I test a regular expression online?

Enter your regex pattern and test string into ZapFile's Regex Tester. It instantly highlights all matches and shows captured groups.

What regex flavors does ZapFile support?

ZapFile's Regex Tester uses JavaScript's built-in regular expression engine, supporting standard regex syntax including lookaheads, capture groups, and all common flags.

Regex Tester

Test and debug regular expressions with live matching

Pattern

Common Patterns

Test String

Highlighted Matches

Matches will be highlighted here as you type.

ReplacePreview a replacement. Use $1, $<name> for groups, $& for the whole match, $$ for a dollar sign.

Frequently Asked Questions

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Highlighted Matches

Frequently Asked Questions

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