Luhn Validator Online for Card, IMEI and Numbers
Check whether a number passes the Luhn algorithm (credit card, IMEI, SIREN…), in your browser.
The Luhn algorithm validates the check digit (credit cards, IMEI, etc.). It does not guarantee a number really exists.
🔒 100% client-side — no data sent
This tool checks whether a number satisfies the Luhn algorithm, used for credit cards, IMEIs, and other identifiers. It catches typos thanks to the check digit. Validation runs 100% in your browser: no number is ever sent or stored.
What is it for?
- ▸ Check that a credit card number has no typo
- ▸ Verify the validity of a mobile phone IMEI
- ▸ Test generated numbers before using them in development
- ▸ Validate the check digit of a Luhn-compliant identifier
FAQ
What is the Luhn algorithm?
It's a checksum formula that detects entry errors in a number using a final check digit computed from the other digits.
Does passing Luhn mean a card is valid?
No, Luhn only checks the number's consistency and catches typos; it does not confirm the card exists or is active.
Is my card number sent anywhere?
No, all computation happens locally in your browser and no number is transmitted or stored.