Are the IBANs in your payment list actually valid?

1. Your list

CSV, TSV, semicolon-separated, or one IBAN per line. The column is found from its header (IBAN, bank account) or by which column looks most like IBANs.

Check list Load a clean example Load an example with errors Clear

Choose a file or paste the text, then click Check list.

Result

The rules, and what they leave out

• Check digits: the ISO 13616 mod-97 test. Catches every single wrong character and every swap of two neighbours. When exactly one adjacent swap would make a bad IBAN valid it is suggested, never applied.
• National check digits (BE, ES, FR, IT): the domestic check inside the account part. An IBAN can pass mod-97 and still be wrong when a generator recomputed the IBAN check digits for a mistyped account; this is reported as a warning.
• Length and shape: total length per country for about 80 countries, and for common ones (Germany, UK, France-length, Netherlands, Spain, Belgium, Austria and others) whether the account part is digits or letters where it must be.
• Cleaned automatically: spaces, hyphens and non-breaking spaces, lower case, a leading apostrophe, Excel's ="…" wrapper and a leading "IBAN:" label.
• Warned: duplicate IBANs, blank cells, and a list that mixes several countries.
• Not checked: whether the account exists or belongs to the payee, BIC/SWIFT codes, plain account numbers and sort codes, sanctions or fraud screening, national check digits for countries other than BE, ES, FR and IT. The country list and lengths are read from memory of the public IBAN registry; confirm against your bank's current documentation.

Common questions

What is the IBAN check and what does it catch?

An IBAN has two check digits right after the country code. Move the first four characters to the end, turn letters into numbers (A=10 to Z=35), and the whole number divided by 97 must leave a remainder of 1. The check catches every single mistyped character and every swap of two neighbouring characters, which are the usual typing errors. It does not prove the account exists.

Why does my bank or payment file reject an IBAN that looks right?

Most often a character is wrong or two are swapped, there are stray spaces or a hidden non-breaking space from a PDF or web page, the letters are lower case, or the IBAN is shorter or longer than the country allows. This tool names which of those it is, with the line number.

Can the tool tell me whether the account exists or whose it is?

No. A valid IBAN is well formed. Whether the account is open, and whether it belongs to the supplier you intend to pay, is only known to the bank. Confirm new or changed bank details with the payee through a channel you already trust before sending money.

How long is an IBAN in each country?

It depends on the country: for example Germany 22, the United Kingdom 22, France 27, the Netherlands 18, Spain 24, Italy 27, Belgium 16, Switzerland 21. The tool checks the length for each country it knows and tells you how many characters are missing or extra.

Is my supplier or payroll list uploaded anywhere?

No. The page reads the file in your browser and a test in the code asserts there are no network calls. Bank details are sensitive; that is why this runs on your device.

What does this not check?

Whether an account exists or matches a name, BIC/SWIFT codes, sort codes and account numbers that are not IBANs, sanctions or fraud screening, whether your bank supports payments to a country, or national check digits for countries other than Belgium, Spain, France and Italy. It reads one column of one file.