It featured around Emails long time back. Well thought, let me not let it fade away in the huge permutations of 1s and 0s. so just packing this cute litil algo on this page to stay ever accessible…
Does this Pic give u indication of money.. cash… There is something very interesting (let alone the cash aspect of the card) about the number pattern in the card. Well Dont worry we are no way close to number thory or something like that. Also knowing this can noway help u tweak card numbers for your use . But then this credit card funda is quite interesting.
The length of a credit card can be either 13 or 15 or 16 characters. The first digit is called the MIF or the major industry identifier. The various values are as follows…


0 
ISO/TC 68 and Other Industries 
1 
Airlines 
2 
Airlines and Other Industries 
3 
Travel and Entertainment 
4 
Banking and Financial 
5 
Banking and Financial 
6 
Merchandizing and Banking 
7 
Petroleum 
8 
Telecommunications and Other Industries 
9 
National ( Local Use ) 
Most of us will carry credit cards beginning with 4 or 5. A petrol card will begin with 7. The first 4 to 6 digits are called the issuers code and they tell us which entity issued us the card. Some well known issuers are as.


Issuer's Code 
Card Issuer 
Number 
3000 to 3059 
Diners Club 
14 
3400 to 3499 
American Express 
15 
3528 to 3589 
JCB 
16 
3890 to 3899 
Carte Blanche 
14 
4000 to 4999 
Visa 
13 or 16 
5100 to 5599 
MasterCard 
16 
5610 
Australian BankCard 
16 
6011 
Discover / Novus 
16

The remaining 1012 bits are the actual credit card number. These numbers are not just randomly generated by the credit card companies but are generated such that they meet a certain rule. This rule or algorithm called the Luhn algorithm. The International Standards Organization (ISO/IEC 78121:1993) and the American National Standards Institute (ANSI X4.13) have now standardized on the above algorithm for credit card number validation.
Lets take a dummy Visa card and apply the Luhn algorithm to it.
4567 1234 5678 9129
We first start from the right and this last digit is called the check sum. We start with the rightmost –1 digit and multiply every other digit by 2.
4 5 6 7 1 2 3 4 5 6 7 8 9 1 2 9
8 12 2 6 10 14 18 4
We then subtract 9 from any number larger than 10. Thus we get.
8 3 2 6 1 5 9 4.
Another way out is by adding the individual digits.
We then add them all up to get
38
We then add all the other digits to get
42
The sum of the two is 80 which will add up to a number divisible by 10. Thus the above algorithm is called the Luhn modulus 10. The last digit is called the check digit as it is the one used to make sure that we get a final number divisible by 10. We have a 90% reliability with the Luhn algorithm. Next time you look at your credit card number don just look at it like a strange combiination of numbers but just note the pattern that it satisfies..
i need algo from this year can you help me??
can u b a bit clear!! i din get what u are asking for.. if u are asking for a code to check if a number satisfies the Credit card number criteria then fine.. i think i have it somewhere…
heh, real nice writeup, i guess the real algo somebody would want is the 2nd part of track2, so cc# = xxxxx, the xxxx part is also a mathemtical algorithm for each instituion???
I would like to know what are the steps in making a track2 algoritm. Is there an universal algorithm for track2 (like Luhn formula )?
hello sir,
we are using tsop as ir receiver, we are having problem with the circuit,since tsop output is active low we are connecting it to 7414 then its output to uln2003 driver and an led at the output of uln2003, we are also connecting a capacitor of 47 micro farad between tsop gnd and vcc pin does this circuit works…..waitin for ur reply
thanking you,
Nice thought Kiran . Can you tel me more on the voltage levels maintained and what exactly you see connecting this?
Very cool
Like this one:
http://www.buscaparejaenlinea.es
oh…
its a vry nice and also helpfull for me..i want to implement it on my project
Interesting knowledge! Never read anything like this before. Thank you for sharing.
Use this mixture over the face as an astringent anytime required.
Let’s see what they had to say and discover some other homemade beauty care ideas too.