Validate a single International Bank Account Number (IBAN) against the official ISO 13616 structure for its country.

What it checks: the country code, total length for that country, the national BBAN structure, and the MOD-97 check digits. When the bank/branch code maps to a known institution, the response also includes the bank name, BIC/SWIFT code, and country.

Returns JSON with valid (boolean), iban, formatted, country, country_name, check_digits, bban, and, when the bank is recognized, bank_name, bic, bank_code, bank_city, sepa and national_check_valid. An invalid IBAN still returns a result, with valid: false, an error message and an error_code (e.g. INVALID_CHECKSUM, INVALID_LENGTH, UNKNOWN_COUNTRY); it does not throw.

Use this when you have one account number to verify. For many IBANs prefer validate_bulk_ibans; to pull IBANs out of prose use extract_ibans_from_text first. No account data is stored; validation runs in memory and is discarded. Requires an API key; a free key from ibanchecker.cash/api-docs covers 100 requests a month.

Validate a batch of up to 100 IBANs in one call, applying the same ISO 13616 checks as validate_iban (country, length, BBAN structure, MOD-97).

Returns JSON with count, valid_count, invalid_count and results, one entry per IBAN in input order, each shaped like a validate_iban result.

Use this instead of calling validate_iban in a loop when checking a list (e.g. a payment file or a column of supplier accounts). Split inputs larger than 100 into multiple calls. Account numbers are validated in memory and never stored. Requires an API key on the Basic plan or above; a free key whose address has a verified ibanchecker.cash account can try it with up to 10 IBANs per call. Each IBAN counts as one request.

Scan a free-form block of text and pull out every candidate IBAN, then validate each one.

Useful for unstructured sources such as emails, invoices, PDFs pasted as text, or chat messages where IBANs appear inline and may be split by spaces or surrounded by other words. Returns JSON with count, valid_count, invalid_count and results, one validate_iban-shaped entry per IBAN found; text containing no IBAN returns an empty list rather than an error.

Use this as the first step when the account number is buried in prose; pass the extracted IBANs to validate_bulk_ibans only if you need to re-check them separately. Input text is processed in memory and not stored. Requires an API key on the Growth plan or above; a free key whose address has a verified ibanchecker.cash account can try it with up to 5,000 characters per call. Each IBAN found counts as one request.

Return the IBAN format specification for a country, covering 92 supported IBAN-using countries.

Returns JSON describing the country's total IBAN length, the BBAN layout (bank code, branch code, and account number positions and lengths), an example IBAN, and the SEPA-membership flag. Use this to understand or display how a country's IBAN is structured, to build input masks, or to explain a validation failure, not to validate a specific number (use validate_iban for that). An unsupported or unknown country code returns an error result describing the problem. Works without an API key, up to 100 requests an hour per IP.

Look up a financial institution by its BIC (Business Identifier Code, also called SWIFT code) and return the matching bank's details.

Accepts an 8-character (head office) or 11-character (branch) BIC. Returns JSON with bic, bic8, bank_name, city, country_code, country_name, sepa, the institution type and its status. Use this to resolve a BIC to a human-readable bank, to confirm a SWIFT code is real, or to enrich a validated IBAN with institution details. An unknown or malformed BIC returns an error result rather than a guess; codes are never fabricated. Requires an API key on the Basic plan or above, or a free key whose address has a verified ibanchecker.cash account.