Which regex flags can I use?

Global, case-insensitive, multiline and dotAll flags are all supported and toggle live as you test.

Can I see which part of the text matched?

Yes, matches are highlighted directly within your sample text as you refine the pattern.

Does it show capture groups?

Yes, capture groups from your pattern are listed separately alongside the full match.

Does Regex Tester upload my files to a server?

No. Regex Tester runs entirely in your browser using on-device processing, your files never leave your device.

Regex Tester

Test regular expressions against sample text.

Runs in your browser

Pattern

//g

gims

Test text

About this tool

Writing a regular expression and confirming it actually matches what you intend needs testing against real sample text, since regex syntax is notoriously easy to get subtly wrong by reading alone. This tool tests regular expressions against sample text, letting you refine a pattern until it matches exactly what you need.

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