Validating telephone numbers
You've correctly identified that it's a tricky problem...
Most cell phones in the US don't require it, and it'll start to baffle the younger generation unless they've dialed internationally.
As per European Union banking standards, from 2004 all banks of european union countries, including switzerland, austria, liechtenstein, and luxembourg implement common eu clearing system, for which account numbers are represented in IBAN format.
The IBAN account number is a series of alphanumeric characters that uniquely identifies an account held at a bank anywhere in the world.
It adds a flag dropdown to any input, detects the user's country, displays a relevant placeholder and provides formatting/validation methods.
005540A1024502601 mod 97 which gives 1 THE RESULT OF VALIDATING AN IBAN MUST ALWAYS BE '1' from the modulo operation Hence, the calculated IBAN number is correct.The main purpose of an IBAN is to promote straight-through processing of international financial transactions, thereby making the transfer of funds between different EU countries quick, fast and more efficient. This concession is not possible for payment transactions done in currencies other than euro. Account Number (12 digits) It is not necessary that, the iban may contain only numbers, but can also have alpha-numeric characters.No bank charges involving IBAN All payment transactions made within european union, quoted with IBAN numbers are charged like domestic payments, if : 1. The SWISS IBAN is made up of the following elements: * a two-letter country code (CH for switzerland) * a two-number check digit (CD) for the entire IBAN * a Basic Bank Account Number (BBAN), no more than 30 characters long, comprising Institution Identification (IID) and Bank Account Number (BAN) Swiss IBAN consists of maximum 21 alphanumeric characters, uniquely identifies the swiss bank, bank clearing number and customers account number, all included under one roof (IBAN format). As you notice from the above parameters, we have all necessary data for iban but 'Control digit' is missing. Goal: To calculate control digit of IBAN from account number, and bc number.Always contact your bank to verify swift, iban or other information used in payments.These parameters of banks are subjected to change from time to time.