Integrate IBAN checks into your software
Try a validation, inspect the response, then connect your application through the API or an existing integration.
Explore the API workflowBankleitzahl 37040044
Commerzbank, Köln
| Bankleitzahl | 37040044 |
|---|---|
| Institution | Commerzbank |
| Short name | Commerzbank Köln |
| BIC | COBADEFFXXX |
| Postcode | 50447 |
| Town | Köln |
| Status | active |
| Successor BLZ | none |
IBAN structure with this code
A German IBAN is DE, two check digits, the eight-digit Bankleitzahl, then the ten-digit account number. The BLZ is what the register can vouch for; the account number is known only to the bank.
DE23 3704 0044 1000 0000 00
Synthetic example: the account part is a placeholder, this IBAN belongs to nobody. It shows where the code sits inside the IBAN.
What the API answers for this code
The block below is the route's own answer, produced by the same code that serves api.ibanforge.com, on the register as of the date shown. Nothing is edited.
{
"valid": true,
"bic": {
"code": "COBADEFFXXX",
"bic8": "COBADEFF",
"bank_name": "Commerzbank",
"city": "Köln",
"source": "Deutsche Bundesbank Bankleitzahlendatei",
"as_of": "2026-10",
"basis": "national_register",
"authoritative": true,
"lei": "851WYGNLUQLFZBSYGB56"
},
"bank_code_check": {
"value": "37040044",
"status": "verified",
"match": "register",
"register": "Deutsche Bundesbank Bankleitzahlendatei",
"authoritative": true,
"institution": {
"name": "Commerzbank",
"street": null,
"post_code": "50447",
"town": "Köln",
"country": "DE"
},
"as_of": "2026-10"
},
"sepa": {
"member": true,
"vop_required": true
},
"issuer": {
"type": "bank",
"name": "Commerzbank",
"classification": "default"
},
"risk_indicators": {
"country_risk": "standard",
"sepa_reachable": true,
"vop_coverage": true,
"test_bic": false
}
}Get this answer from your own software
The IBANforge API checks an IBAN and names the bank behind it, with its BIC when one is known, reading national registers such as the one on this page. Two ways to start without paying:
Keyless trial
Send an IBAN to POST /v1/iban/validate with no key at all, up to 25 times a week, on that route only. With this page’s example IBAN:
curl -X POST https://api.ibanforge.com/v1/iban/validate \
-H "Content-Type: application/json" \
-d '{"iban":"DE23370400441000000000"}'Free key
200 requests a month on every endpoint once you add an e-mail address and confirm the code sent to it. With no address and no card, it starts at 25 requests a month, straight away.
Other codes of the same institution
Put these checks to work
Choose a first step for your software or your supplier file.
Check a supplier file
Upload a CSV or Excel file and preview the findings for free. Purchase the annotated workbook if you need the full report. No account or subscription required.
Explore the file auditAvailable bank information varies by country and source. These checks do not confirm the account holder or guarantee that a payment will succeed.
Source: Deutsche Bundesbank Bankleitzahlendatei, register as of 2026-10.