Which regex engine does this use?

This tester uses the browser's JavaScript RegExp engine. Some features differ from PCRE or other flavors.

Yes. All testing is done locally in your browser. Nothing is sent to our servers unless you export patterns manually.

Can I save frequently used patterns?

Yes. Save and load regex patterns locally in your browser, and export/import them as JSON files.

Regex pattern

gimsuy

Save / Load

Import

No saved patterns

Test text

No matches

Type or paste text here to test your regex.
Example: hello world 123 hello.

Test and debug regular expressions with live highlighting, group inspection, replace-preview, and pattern management - all in your browser.

Enter a pattern. Type your regex in the pattern field. Use flags to control behavior (g,i,m,s,u,y).
Paste test text. The tester highlights all matches and shows capture groups live.
Use replace. Test replacement strings using $1, $2, $& and preview the output before applying.
Save patterns. Save commonly used regexes locally and export them for sharing or backup.

Which regex engine does this use?: This tester uses JavaScript's RegExp engine in the browser. Behavior may vary for PCRE, Python, or other flavors.
Is my data private?: Yes - all testing runs locally; nothing is uploaded unless you export patterns.
Can I save patterns?: Yes - save, load, export and import patterns using JSON files.