Hungary IBAN validator
How the IBAN format works
- Format
- HU + 2 check digits + 24-digit bank/account number (28 chars)
- Example
- HU42117730161111101800000000
Things to watch for
- 28 characters total, all numeric
- Includes its own internal check digits beyond the IBAN check digits
^HU[0-9]{2}[0-9]{24}$A Hungarian IBAN is 28 characters — among the longest in Europe — made up of “HU”, two check digits, and a 24-digit block that carries the bank code, branch code, and account number together. What sets Hungary apart is that this 24-digit block isn’t just raw account data: Hungary’s pre-IBAN domestic numbering scheme already embedded its own internal check digits at specific positions within the block, a layer of validation that exists independently of the mod-97 checksum the IBAN format adds at the front. Anyone paying a Hungarian supplier, sending forint-denominated invoices, or converting an old domestic account number to IBAN needs all 28 characters correct, since a single dropped digit shifts everything after it.
How this validator works
This tool checks the “HU” prefix and confirms the trailing block is exactly 24 digits, then runs the real mod-97 checksum (ISO 7064) Hungarian banks use to generate a valid IBAN — entirely in your browser, nothing sent to a server, no signup, result as you type.
What a pass doesn’t tell you
A pass confirms the 28 characters are correctly formed and internally consistent at the IBAN level — not that the account exists, is open, or belongs to whoever you expect, and not a separate recomputation of Hungary’s internal domestic check-digit positions. This tool does no bank-code-to-bank-name lookup and never contacts Magyar Nemzeti Bank or any commercial bank. If a Hungarian IBAN fails, a single digit shifted or dropped anywhere in the 24-digit block is the most likely cause — recheck it against the original source in short segments rather than all at once.
Scope: Hungarian IBAN structure and mod-97 checksum validation only — not payment processing, bank-name resolution, or confirming an account is active, none of which a client-side check can establish. Use this validator to catch a typo before a transfer fails; use your bank to confirm the account itself.
Content last reviewed 2026-07-07.
IBAN FAQ
How long is a Hungarian IBAN and what does it contain?
28 characters — one of the longest IBANs in Europe: 'HU', two check digits, and a 24-digit block covering the bank code, branch code, and account number, all numeric — for example HU42117730161111101800000000.
What does it mean that Hungary has 'its own check digits per block'?
Beyond the two mod-97 check digits the IBAN format itself adds after 'HU', Hungary's domestic account-number scheme (predating IBAN) embeds its own internal check digits inside specific positions of the 24-digit block — so a Hungarian account number is validated twice over, once domestically and once by the IBAN checksum.
Does this tool independently recompute Hungary's domestic check-digit blocks?
This tool runs the IBAN-level mod-97 (ISO 7064) checksum across all 28 characters. It doesn't separately isolate and recompute Hungary's internal domestic check-digit algorithm as a distinct step, and it doesn't confirm the account is open or belongs to anyone — that requires your bank or Magyar Nemzeti Bank.