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Card Number Formatter

Format card numbers with the right spacing per brand (Amex 4-6-5, others 4-4-4-4).

Tool inputs stay in your browser · optional AI search sends your query

Good to know: Detects the brand per line. Non-digit characters are removed first.

How to use it (step by step)

  1. 1Type or paste your text into the “Input” box. There is already an example in it so you can see how it works; press Clear to start with your own.
  2. 2Choose your settings: “Separator”.
  3. 3The answer appears right away in the “Result” box. No button needed.
  4. 4Press Copy and paste the result wherever you need it.

Words to know

Beautify / format
Adding line breaks and indentation so code is easy for humans to read. It does not change what the code does.

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