Check and Validate
Free validators for IBAN, VAT, card, ID, and ISBN numbers. No sign-up needed.
A set of focused tools for checking the numbers behind bank accounts, cards, tax records, identity documents, and books. They cover the IBAN, UK VAT numbers, credit card numbers, the Spanish DNI and NIE, UK driving licences, the Romanian CNP, and the ISBN. Each one runs entirely on this page, uses the official algorithm, and explains what it found. There is nothing to install and no account to create.
Validators
European IBAN Validator
Validate an IBAN with the mod-97 checksum and the official per-country length, and see exactly which check failed.
SWIFT / BIC Code Checker
Check the structure of a SWIFT/BIC code and its country, and break it into its bank, location, and branch parts. Format only, no bank lookup.
UK VAT Number Validator
Check a UK VAT number with the HMRC modulus-97 check digit algorithm, including the newer 9755 variant.
EU VAT Number Validator
Check the format of a VAT number for any EU country (plus Northern Ireland). Format check only; confirm it is active with VIES.
US EIN Format Validator
Check that a US EIN has the NN-NNNNNNN format and a valid IRS prefix, plus a guide on how to find your EIN.
Credit Card Number Validator
Check whether a card number is mathematically valid with the Luhn algorithm and see its likely network. Nothing is ever sent anywhere.
US Routing Number (ABA) Validator
Validate a US bank routing number with the 9-digit ABA checksum, and see its Federal Reserve region.
Spanish DNI/NIE Calculator
Work out the check letter for a Spanish DNI or NIE, or confirm whether the letter on an existing document is correct.
UK Driving Licence Decoder
Decode the date of birth and sex embedded in a 16-character UK driving licence number, and check its structure.
Romanian CNP Validator
Check the structure and control digit of a Romanian CNP, and read back the birth date, sex, and county it encodes.
US SSN Format Validator
Check whether a US SSN has a valid structure (area, group, and serial rules). Format only, private, no lookup of any person.
ISBN Validator
Validate an ISBN-10 or ISBN-13 check digit, and convert a valid ISBN-10 into its ISBN-13 form.
This site is available in English, Romanian, and Spanish. Use the language links in the header to switch, and you will land on the same tool in the language you choose.