ISO-0 (Format 0)

Is the first and most common PIN block encoding  format based on ISO 9564 - an international standard for personal identification number (PIN) management and security in retail banking.

Calculation steps:

1. Prepare a PIN - L is length of the PIN, P is PIN digit, F is padding value "F"

   1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16
   0	L	P	P	P	P	P/F	P/F	P/F	P/F	P/F	P/F	P/F	P/F	P/F	P/F

   
   

2. Prepare PAN - take 12 rightmost digits of the primary account number (excluding the check digit)

   1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16
   0	0	0	0	PAN	PAN	PAN	PAN	PAN	PAN	PAN	PAN	PAN	PAN	PAN	PAN

   
   

3. XOR both values

   1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16
   0	L	P	P	P	P	P/F	P/F	P/F	P/F	P/F	P/F	P/F	P/F	P/F	P/F
   XOR	XOR	XOR	XOR	XOR	XOR	XOR	XOR	XOR	XOR	XOR	XOR	XOR	XOR	XOR	XOR
   0	0	0	0	PAN	PAN	PAN	PAN	PAN	PAN	PAN	PAN	PAN	PAN	PAN	PAN

   
   

Example:

PIN blocks: PIN block encrypt operation finished
****************************************
PAN:            43219876543210987
PIN:            1234
PAD:            N/A
Format:         Format 0 (ISO-0)
----------------------------------------
Clear PIN block:0412AC89ABCDEF67

PIN blocks: PIN block decode operation finished
****************************************
PIN block:      0412AC89ABCDEF67
PAN:            43219876543210987
PAD:            N/A
Format:         Format 0 (ISO-0)
----------------------------------------
Decoded PIN:    1234