Regex Builder

Describe what you want to match in plain English. Get a working regex for your language, explained piece by piece, checked against your own test cases.

What do you want to match?

Plain English is fine. Be as specific as you can about the format.

Examples that should matchOptional

Optional but recommended. One example per line.

Examples that should NOT matchOptional

Optional. One example per line.

Regex flavor

Syntax differs between engines (named groups, lookbehind support), so pick the one you are actually using.

Free to try, no sign-up needed

Your text isn't stored. It's sent to Anthropic to generate your result, then discarded. Privacy

Prefer to write it yourself? Use the free prompt.

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