Guide
Build, test, and debug regular expressions right in your browser — like a lightweight regex101. Type a pattern, paste some test text, and every match is highlighted instantly. Nothing is uploaded; your pattern and text never leave your device.
How to use
- Enter your pattern in the
/ … /field at the top. - Toggle the flags you need: g (find all), i (ignore case), m (multiline), s (dot matches newline), u (unicode).
- Paste the text you want to search into Test string.
- Matches are highlighted, listed one by one, and capture groups are broken out per match.
- Optionally type a Replace string (use
$1,$2,$<name>) to preview a find-and-replace without touching your original text.
Handy for marketing & ops work
Regular expressions quietly power a lot of day-to-day marketing tasks. Use this tester to get a pattern right before pasting it where it counts:
- GA4 / Google Tag Manager — validate the regex behind a filter, trigger, or channel grouping (e.g. matching a set of landing-page paths).
- UTM & query strings — confirm a pattern captures
utm_source,utm_campaign, and friends correctly. - List clean-up — pull every email, URL, phone number, or hashtag out of a messy block of text.
- Find & replace — reshape exported data or copy with capture-group references.
Quick start with presets
Not sure where to begin? Click any Common pattern chip (emails, URLs, UTM parameters, dates, prices, hex colors…) to load a ready-made pattern together with matching sample text, then tweak it to fit your case.
Note: this tester uses the JavaScript regex engine. Everyday patterns behave the same across GA4, GTM, and Looker Studio, but confirm advanced constructs (lookbehind, backreferences) in the destination tool.
