Card Number Validator (Luhn)
Validate card numbers with the Luhn checksum and detect the brand (Visa, Mastercard, etc.). Useful for payment development test data. Nothing leaves your browser.
FAQ
Does 'valid' mean the card actually works?
No. The Luhn checksum only catches typos in the number format. Only the issuer can confirm whether a card is real and active.
What is this tool for?
Checking that payment-dev test numbers (like 4111 1111 1111 1111) are well-formed, or catching typos in manually entered numbers.
Are the numbers sent to a server?
No. Everything happens entirely in your browser and nothing is stored.
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