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Regex tester & explainer

Run a JavaScript regex against text (sandboxed with a timeout) and get a token-by-token explanation.

Result

Run the tool to see results here.

About Regex tester & explainer

Regex tester & explainer is a free online developer tool. Run a JavaScript regex against text (sandboxed with a timeout) and get a token-by-token explanation.

Enter your input, adjust the options (pattern, flags and explain) and run it. The result appears right next to the form, is never stored, and you can copy or save it in one click. No account is needed.

How to use Regex tester & explainer

  1. Type or paste your input into the form.
  2. Choose the options you need: pattern, flags and explain.
  3. Press Run, or use Ctrl/⌘ + Enter.
  4. Copy or save the result from the panel on the right.

Regex tester & explainer FAQ

What does Regex tester & explainer do?

Run a JavaScript regex against text (sandboxed with a timeout) and get a token-by-token explanation.

Is Regex tester & explainer free to use?

Yes. Regex tester & explainer is free, with no sign-up or account required.

Is my data safe?

Results are never stored. See our privacy policy for details.

What options does Regex tester & explainer have?

You can set: Pattern, Flags and Explain.

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