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Check accounts and convert IBANs
Czech and Slovak account conversion and international mod 97 checks without uploading inputs.
Your input stays in your browser
Account number / bank code → IBAN
IBAN → Account number / bank code
How it works
CZ and SK IBANs have 24 characters: country (2), check digits (2), bank code (4), prefix (6), account (10). Domestic components use mod 11 and IBAN uses mod 97. Bank names come from a dated snapshot. A correct number does not establish the recipient. Other IBANs receive general shape and mod 97 checks only.
Bank directory snapshot: .
Inputs stay in your browser. Calculations do not establish company existence, tax registration, account existence or recipient identity.
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