IBAN check and IBAN from reg. no.
Check that an IBAN is correctly formed, or turn a Danish reg. no. and account number into an IBAN. Runs in your browser, nothing is sent anywhere.
Paste an IBAN to check it.
What this does and does not tell you
It checks the maths, not the owner
The check digits prove the number is internally consistent, so a typo is caught. It cannot tell you whether the account exists or who it belongs to. Only the bank can confirm that.
Danish account numbers on their own
We do not give a pass or fail on a bare Danish reg. no. and account number. The control rules differ from bank to bank and are not published in one place, so a verdict would risk calling a real account wrong.
Always confirm large payments
For a payment that matters, confirm the details with the recipient through a channel you already trust. A correctly formed IBAN can still be the wrong account.
Questions about IBAN
What is an IBAN?
An International Bank Account Number. It is your national account details written in an international format, so a bank abroad can route the payment. The layout is set by the ISO 13616 standard, and the two digits after the country code are a checksum that catches typos.
What does a Danish IBAN look like?
A Danish IBAN is 18 characters: DK, two check digits, your 4 digit reg. no. and your 10 digit account number. If your account number is shorter, it is padded with leading zeros.
Where do I find my IBAN?
In your online bank, usually under account details, or on a bank statement. You can also build it here from your reg. no. and account number, since the Danish format is fixed.
Do I need an IBAN to invoice abroad?
Usually yes. For payments from another country, the sender normally needs your IBAN and often the BIC or SWIFT code of your bank. Putting both on the invoice saves a round of emails.
Does a valid IBAN mean the account exists?
No. The check confirms the number is correctly formed and free of typos. Whether the account is open, and who owns it, only the bank can confirm.
Is anything sent to SEJR?
No. The check runs entirely in your browser. Nothing you type leaves your device.
The format follows ISO 13616 and the checksum follows ISO 7064 (MOD-97-10), both international standards.
Invoicing abroad? Get paid just as easily.
SEJR Pay lets you take card, MobilePay, Apple Pay and Google Pay, with the money in your account the next banking day.
See SEJR Pay