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<iframe src="https://devtoolbox.dedyn.io/tools/regex-explainer" width="100%" height="700" frameborder="0" title="Regex Explainer"></iframe>

Regex Explainer

Paste any regular expression and get a plain English, token-by-token explanation of what it does. Understand complex patterns without guesswork. Everything runs in your browser — your regex is never sent to a server.

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Frequently Asked Questions

How does the Regex Explainer work?
The Regex Explainer parses your regular expression token by token and translates each part into plain English. It identifies character classes, quantifiers, anchors, groups, lookaheads, and other regex constructs, then describes what each one matches.
What is the difference between a regex explainer and a regex tester?
A regex tester runs a pattern against sample text and shows you what matches. A regex explainer breaks down the pattern itself and tells you what each part means in plain English, helping you understand how the regex works without needing test data.
Can this tool explain complex regex with lookaheads and groups?
Yes. The explainer handles capturing groups, non-capturing groups, positive and negative lookaheads, positive and negative lookbehinds, backreferences, named groups, and nested constructs. Each is identified and described in the token breakdown.
Does the regex explanation run on the server?
No. The entire explanation is generated client-side in your browser using JavaScript. Your regex patterns are never sent to any server, so your data stays completely private.
Keyboard Shortcuts
Ctrl+Enter Explain regex
Ctrl+Shift+C Copy output
Ctrl+L Clear