Luhn check

This tool adds a check-digit to an entered number. This algorithm is used in banking and for IMEI numbers, National Provider Identifier numbers in the USA, or Canadian Social Insurance Numbers.

This check-digit calculator adds a check-digit to a number based on the luhn check-digit algorithm. Enter your number without the check digit in the top field and it will be added in the field below.

Enter input number:
Number with check digit:

Cryptomathic is one of the world's leading providers of security solutions to businesses across a wide range of industry sectors including finance, smart card, digital rights management and government. Cryptomathic provides cryptographic solutions for Authentication & Signing, EMV, CA-Compliance, Key Management, Public Key Infrastructure and ID Issuing.

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