Text & Code Diff Checker
Compare text, code, or JSON and highlight added and removed content. Export a readable difference report.
Developer UtilitiesOpen tool
Regex Tester
Test regex patterns with live highlighting and 12 SEO presets for slugs, UTM params, meta tags, and more.
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Test Text
Matches
Enter a valid regex pattern to see matches
Regex Tester
A JavaScript regex playground with 12 built-in presets for common SEO tasks — extracting URL slugs, query parameters, UTM values, meta tags, canonical URLs, internal links, image sources, and more. Supports match highlighting, numbered capture groups, named groups, and replace testing.
12 SEO Presets
One click loads a pattern and sample text for URL slugs, UTM params, meta tags, HTTP status codes, emails, and more.
Live Highlighting
Every match is highlighted in the test text as you type, making it easy to verify your pattern scope.
Capture Groups
See each numbered and named capture group value per match. Use $1, $2 in the replace box to reference them.
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Need help with inputs or downloads? Read the help page.