How do I enter a regex?
Use Pattern: /your-pattern/flags on the first line, then add a blank line and the text to test.
Text tool
Regex Tester
Test regular expressions against text and inspect matches, groups and indexes.
Common use cases
- Clean copied notes and prompts.
- Sort, replace and deduplicate text lists.
- Prepare content for docs and development tasks.
Example input
Pattern: /json/gi
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TextFreeFAQ
Are capture groups shown?
Yes. Capture groups are shown when the regex includes them.
Does it modify text?
No. Regex Tester only reports matches. Use Find and Replace Text when you want to replace matches.