Tools to check Luhn generated numbers. The Luhn algorithm (also called modulo 10 or mod 10) is a checksum formula for numbers/digits used with credit card or administrative numbers.

Luhn Number Checksum - dCode

Tag(s) : Checksum,Algorithm,Arithmetics,Mathematics

dCode is free and its tools are a valuable help in games, puzzles and problems to solve every day!

You have a problem, an idea for a project, a specific need and dCode can not (yet) help you? You need custom development? *Contact-me*!

This page is using the new English version of dCode, *please make comments* !

Sponsored ads

Tools to check Luhn generated numbers. The Luhn algorithm (also called modulo 10 or mod 10) is a checksum formula for numbers/digits used with credit card or administrative numbers.

This algorithm allows checking credit card numbers MasterCard/AMEX/Visa of IMEI codes for example by using a control key checksum. If one character is badly written, in the Luhn algorithm can detect it.

Let 12345674 be a valid card number, 1234567 is the main original number and 4 is the checksum.

If a user enter 13245674, then the program calculates the checksum for 1324567 and finds 5 instead of 4 expected, the number is invalid and so has been badly typed.

The algorithm starts by the end of the number, from the last right digit to the first left digit. One realizes a sum of digits by multiplying by 2 all digits of even rank. If the double is equal or superior to 10, one replaces it by the sum of its digits. The control digit number is equal to (10-sum%10) % 10.

Let the number be 853X, with X=0, the digit we want to calculate.

One takes the digit 3, doubled, 3*2 = 6,

One takes the digits 5, not multiplied by 2

And one takes the 8, multiplies it by 2 : 8*2=16 and 1+6=7 to get 7.

The sum is 6+5+7 = 18. As 18 modulo 10 = 8, one calculated (10 - 8) %10 = 2, 2 is the digit checksum control.

So 8532 is valid.

dCode retains ownership of the source code of the script Luhn Number Checksum. Except explicit open source licence (indicated Creative Commons / free), any algorithm, applet, snippet, software (converter, solver, encryption / decryption, encoding / decoding, ciphering / deciphering, translator), or any function (convert, solve, decrypt, encrypt, decipher, cipher, decode, code, translate) written in any informatic langauge (PHP, Java, C#, Python, Javascript, etc.) which dCode owns rights can be transferred after sales quote. So if you need to download the Luhn Number Checksum script for offline use, for you, your company or association, see you on contact page !

luhn,card,credit,imei,mastercard,amex,visa,american,express,sum,check,checksum,modulo,10,mod,account,validation,digit,number,algorithm,key,ccv,generator

Source : http://www.dcode.fr/luhn-algorithm

© 2017 dCode — The ultimate 'toolkit' to solve every games / riddles / geocaches. dCode