IBAN is stands for Internal Bank Account Number, A numbering system to identify bank account worldwide. IBAN is account number using internationally for the electronic transactions. IBAN is mostly use to receive the payment from out of country. Mostly for receving payment from foreign contries they ask for SWIF code & IBAN of your bank account.
Some banks are providing online web services to get the IBAN against your bank number as Alied Bank Ltd is giving you quick & easy way to get the IBAN Number by just visit this page Alied bank IBAN generate you just have to enter your account # and system will tell you the IBAN of your account.
You may get the IBAN of your standar charted bank account from this url standard charted IBAN number
HBL IBAN information can be found here. HBL IBAN number
As mostly all banks have the IBAN number so simply by calling to your bank you can get the IBAN of your bank account #.