IBAN Validator

Anatomy of a Ukrainian IBAN

29 characters, each group with its own purpose. Take UA21 3223 1300 0002 6007 2335 6600 1:

• UA — the ISO 3166 country code. Two letters, always first.
• 21 — check digits. Computed from the rest of the number with the MOD-97 algorithm; they are what lets a typo be caught without contacting the bank.
• 322313 — the bank code, known in Ukraine as MFO. Six digits, which the tool uses to label the institution: 305299 is PrivatBank, 300465 Oschadbank, 322001 Universal Bank (monobank).
• 0000026007233566001 — the account number within the bank, 19 characters. Leading zeros are not an error but padding to the standard length: older accounts were shorter.

IBAN length differs by country: 29 in Ukraine, 22 in Germany, 28 in Poland, 22 in the UK. The tool knows the lengths for 70 countries and checks that first, then the checksum.

How the check works

MOD-97 is the same algorithm in every country. The first four characters move to the end, letters become numbers (A=10, B=11 … Z=35), and the resulting long number is divided by 97. A remainder of 1 means the number is written correctly. A single wrong character or two swapped digits almost always produce a different remainder, so the check catches typical input errors.

What it cannot do: tell whether the account exists, is open, or who owns it. Only the bank knows that. A valid IBAN means "no typo in the number", nothing more.

Payment QR code

Once a Ukrainian IBAN validates, a form appears below: recipient, EDRPOU or tax number, amount and purpose. The button builds a QR code in the National Bank of Ukraine standard, the one read by Privat24, monobank, Oschad 24/7 and other banking apps: the payer scans it and every field of the transfer form is filled in without typing.

Where it helps:

• On invoices and acts — the client pays in ten seconds instead of retyping 29 characters.
• On a website or profile — for fundraising, donations, paying for services without integrating a payment gateway.
• In a messenger — send a picture instead of dictating details.

The amount is optional; if left blank the payer enters it. The payment purpose is required: without it a bank will not process a transfer to a legal entity. The code is built in the browser and nothing is sent anywhere. Before printing a QR, scan it with your own banking app so you see exactly what the payer will see.

Common mistakes when entering an IBAN

• Letter O instead of zero. After UA there are only digits. If the tool says "invalid" but the number came from a document, check this first.
• A missing or extra digit. The tool reports "wrong length" with the expected count; count the groups of four.
• An old account number without IBAN. Until 2019 Ukrainian accounts were 14 digits and details were given as "account + MFO". Such a number must be converted to IBAN by the bank or the calculator on its website.
• Spaces and hyphens. Enter them however you like; the tool ignores them and shows the number in print format, in groups of four.

The IBAN is valid but the payment fails

If the checksum passes and the bank still rejects the transfer, the number is not the problem. The usual causes: the account is closed; the recipient is a legal entity and the purpose field is empty or not what its bank expects; the amount exceeds the limit for unidentified transfers; the account is in foreign currency and the transfer is in hryvnia. In each case the answer comes from the recipient's bank, not from validating the number.

For company details there is also the EDRPOU and tax number check, which catches typos by checksum in the codes that sit next to the IBAN on every invoice.