IBAN Validator, Formatter & Bulk Checker
Paste one IBAN or a whole list. Each number is checked against the official ISO 13616 mod-97 formula, then broken down into its country, bank, branch and account parts - entirely inside your browser, so no account number ever leaves your computer.
Every check runs in your browser using the ISO 13616 MOD 97-10 formula. No account number is uploaded, logged or sent anywhere.
Paste an IBAN to check it
IBAN length & format by country
- Total length
- 22 characters
- Account layout
- 8!n10!n
- Example
- DE89 3704 0044 0532 0130 00
- Currency
- EUR
How the mod-97 check actually works
Every IBAN carries two check digits in positions three and four. Validating one is a fixed four-step procedure defined by ISO 13616 and published in the SWIFT IBAN Registry: confirm the length matches the country's registered length, move the first four characters to the end, replace each letter with two digits (A = 10 through Z = 35), and take the resulting integer modulo 97. A genuine IBAN always leaves a remainder of exactly 1.
That single test catches every single-character typo and almost every transposition - which is precisely why it exists. What it cannot do is tell you whether the account is open, who owns it, or whether the bank will accept a transfer. A valid checksum means “this number is internally consistent”, nothing more.
This tool also checks the national account layout on top of the checksum. Germany's BBAN is 18 digits, the Netherlands uses four letters then ten digits, France mixes both - so a capital O typed where a zero belongs gets caught here even when the checksum happens to pass.
The country table covers all 116 IBAN-issuing countries, including expected length, SEPA membership and where the bank and branch identifiers sit inside each country's account number.
अक्सर पूछे जाने वाले प्रश्न
Is my IBAN sent to a server?
No. The entire check - mod-97 checksum, length, national layout and the bank/branch breakdown - is JavaScript running in your browser. There is no network request, nothing is logged, and nothing is stored. You can disconnect from the internet and this page still works.
Comment vérifier un RIB ou un IBAN gratuitement ?
Collez l'IBAN dans le champ ci-dessus : la clé de contrôle mod-97 est vérifiée instantanément, et le code banque, le code guichet et le numéro de compte sont affichés séparément. Pour un RIB français, l'IBAN fait 27 caractères et commence par FR. Tout est calculé dans votre navigateur, aucune donnée bancaire n'est transmise.
Wie kann ich eine IBAN kostenlos prüfen?
IBAN einfügen - die Prüfsumme nach ISO 13616 (Modulo 97) wird sofort berechnet und Land, Bankleitzahl und Kontonummer werden angezeigt. Eine deutsche IBAN hat 22 Zeichen. Die Prüfung läuft vollständig im Browser, es werden keine Bankdaten übertragen oder gespeichert.
¿Cómo comprobar un IBAN?
Pega el IBAN y se validará al instante con el algoritmo mod-97 de la norma ISO 13616, mostrando el país, la entidad, la oficina y el número de cuenta. Un IBAN español tiene 24 caracteres. Todo el cálculo ocurre en tu navegador, sin enviar datos bancarios a ningún servidor.
Come verificare un IBAN?
Incolla l'IBAN: il codice di controllo mod-97 viene verificato subito e il codice ABI, il CAB e il numero di conto vengono mostrati separatamente. Un IBAN italiano è lungo 27 caratteri. Tutto viene calcolato nel browser, nessun dato bancario viene trasmesso.
Can I bulk validate IBANs from a CSV?
Yes. Switch to bulk mode and paste a plain list, or a whole CSV or TSV export with any number of columns - the column containing IBANs is detected automatically. You get a per-row valid/invalid verdict with the specific reason for each failure, a summary count, a breakdown by country, duplicate detection, and a CSV export of the whole table. Up to 20,000 rows are processed in chunks so the page never freezes.
What does "checksum failed" mean if the IBAN came straight off an invoice?
It means the digits are internally inconsistent, so at least one character is wrong. The usual causes are OCR mistakes (0 read as O, 1 as I, 5 as S), a transposed pair of digits, or a truncated number. Don't guess a correction - a wrong IBAN can send money to a real stranger's account. Ask the sender to confirm it.
Does a valid IBAN mean the account exists?
No, and this is the single most important limitation. The checksum only proves the number is well-formed. Millions of syntactically valid IBANs have never been issued. Only the receiving bank can confirm an account exists, and only a Confirmation of Payee / VoP check can confirm the name on it matches who you think you're paying.
Why does the bank or branch code show as empty for some countries?
The SWIFT IBAN Registry records where the bank and branch identifiers sit inside the account number for most, but not all, countries. Where a country hasn't published those offsets, this tool shows the whole BBAN rather than inventing a split.
Which countries are supported?
All 116 countries in the IBAN registry, including every SEPA country plus non-SEPA IBAN users like Turkey, Israel, Saudi Arabia and Brazil. A handful of countries use IBANs in practice without being formally registered with SWIFT; those are validated too but flagged as unofficial.