Regex

AI Regex Generator

Describe what you want to match in plain English — get a working regular expression with explanations and examples.

Your description is sent to our AI service to generate the pattern. Generated patterns are yours to keep; sample text you test stays in your browser.

AI Regex Pattern Generator

Describe what you want to match and get a perfect regex pattern with explanations

How to use

  1. Describe the text you want to match in natural language, e.g. 'a Chinese mobile phone number'.
  2. Click Generate and review the returned pattern with its explanation.
  3. Test it against sample strings right in the result area.
  4. Copy the pattern into your code, or save it to your library when signed in.

Why generate regex instead of writing it?

Regular expressions are compact and powerful, but their syntax is famously hard to memorize: character classes, quantifiers, lookarounds, and escaping rules all interact. For one-off tasks — validating an email field, extracting dates from logs, splitting CSV lines — describing the intent and reviewing a generated pattern is usually faster than composing it by hand.

Treat generated patterns like any AI output: read the explanation, test edge cases, and understand every token before shipping it. The included tester lets you verify matches immediately, and our cheat sheet explains any syntax you don't recognize.

Free visitors get a daily allowance of generations; signed-in users with a subscription get higher limits. The rest of the RegexBox toolbox — tester, templates, cheat sheet — is free and unlimited.

Examples

Input validation

Ask for 'a password with 8+ characters, at least one digit and one uppercase letter' and get a lookahead-based pattern ready for your form validation.

Log parsing

Describe your log line format and receive a pattern with named capture groups for timestamp, level, and message.

Data extraction

'Extract all hashtags from a tweet' becomes a short pattern like #[\w]+ you can run over any text.

Frequently Asked Questions

Is the generated regex guaranteed correct?+
No. AI-generated patterns are a strong starting point but must be tested against your real data, especially edge cases. Use the built-in tester and the Regex Tester page before deploying.
Which regex flavor does it produce?+
Patterns target the JavaScript/PCRE common core. Language-specific quirks (Java, Python, Go) are noted in the explanation when relevant — see our Java and Python regex guides.
How many generations can I use?+
Free visitors get a small daily allowance; accounts with a subscription get extended limits. All other tools on RegexBox are free and unlimited.
I already have a pattern — can I understand it instead?+
Yes. Paste it into the Regex Tester to get a token-by-token explanation and live match results.
Where can I learn regex syntax?+
Start with our Cheat Sheet and browse the Template Library for ready-made patterns.

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