Regex Playground
A scratchpad for regular expressions — try things out, keep a local history of what you have written, and share a whole workspace with a link. Runs entirely in your browser using JavaScript's native RegExp, so nothing is ever sent to a server.
Looking for the documented tool with step-by-step guidance and FAQs? That is theregex tester.
How to Use the Online Regex Playground & Tester
The Build Regex Playground is an offline-first, client-side regular expression utility. It compiles and evaluates your patterns instantly in your browser using JavaScript's native RegExp engine, ensuring your code snippets and sample text are never sent over the network.
1. Define Your Regex Pattern
Type your regular expression in the pattern input box (placed between the slash separators). Click the flags toggle next to it to select modifiers like g (global match), i (case-insensitive), m (multiline match), or u (unicode support).
2. Input Test Strings
Paste or type the text you want to search against into the "Test text" box. The editor automatically highlights matched segments, colored highlight markers, and matched capture groups in real-time.
3. Inspect Match Results
The Results panel displays index positions, full match values, and captured sub-strings. If your pattern contains named capture groups, they are automatically parsed out and displayed alongside their match labels.
4. Save, Share, or Export
Use the toolbar to copy your regex to your clipboard, save it to your local browser storage history, or click the "Share" button to copy a unique URL that encodes your current workspace for team members.
Keep Going
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