Best Free Online Developer Tools to Use in 2026
A practical, opinionated list of the best free online developer tools worth using in 2026, organized by category so you can find what you need fast.
Aug 08, 2026
IBAN Validator
Validate International Bank Account Numbers with checksum verification, detect country, bank code, and branch details.
IBAN Validator
Enter an IBAN to validate. Spaces are automatically removed.
Country
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Length
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Checksum
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Formatted
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Structure
- Enter an IBAN — Type or paste an International Bank Account Number. Spaces are removed automatically.
- Instant validation — The IBAN is validated in real-time using the MOD-97 checksum algorithm with country-specific structure checks.
- View details — See the country, length, checksum, bank code, branch code, and account number details.
- Try examples — Click the Example button to test with valid sample IBANs from different countries.
All validation is performed 100% client-side in your browser. No bank data is sent to any server.
What Is an IBAN?
The International Bank Account Number (IBAN) is a standardized international numbering system for bank accounts, used to facilitate cross-border transactions. It was developed by the International Organization for Standardization (ISO) under ISO 13616.
An IBAN consists of up to 34 alphanumeric characters, beginning with a two-letter country code, followed by two check digits, and a Basic Bank Account Number (BBAN) that varies by country. The BBAN typically includes a bank identifier, branch code, and account number.
The IBAN system is used in over 100 countries worldwide, including all European Union members, and is essential for SEPA (Single Euro Payments Area) transfers.
Common IBAN Formats
| Country | Code | Length | Format |
|---|---|---|---|
| Germany | DE | 22 | DEkk BBBB BBBB CCCC CCCC CC |
| France | FR | 27 | FRkk BBBB BGGG GGCC CCCC CCCC CXX |
| United Kingdom | GB | 22 | GBkk BBBB SSSS SSCC CCCC CC |
| Italy | IT | 27 | ITkk CCCC CCCC CCCC CCCC CCCC CXX |
| Spain | ES | 24 | ESkk BBBB GGGG XXCC CCCC CCCC |
| Netherlands | NL | 18 | NLkk BBBB CCCC CCCC CC |
| Belgium | BE | 16 | BEkk BBBC CCCC CCXX |
| Switzerland | CH | 21 | CHkk BBBB BCCC CCCC CCCC C |
| Saudi Arabia | SA | 24 | SAkk BBCC CCCC CCCC CCCC CCCC |
| United Arab Emirates | AE | 23 | AEkk BBCC CCCC CCCC CCCC CCC |
B = Bank code, C = Account number, G = Branch code, S = Sort code, X = National check digits, k = Check digits
What does IBAN stand for?
IBAN stands for International Bank Account Number. It is a standardized international numbering system for identifying bank accounts across national borders.
How is an IBAN validated?
An IBAN is validated using the MOD-97 algorithm. The first four characters (country code and check digits) are moved to the end, letters are converted to numbers (A=10, B=11, ..., Z=35), and the resulting number must be divisible by 97.
Is IBAN the same as a bank account number?
No. An IBAN encodes your existing bank account number along with country and bank identifiers. It is an extension of your national account number, not a replacement.
Do all countries use IBAN?
No. IBAN is mainly used in Europe, the Middle East, and parts of Africa and the Caribbean. The US and Canada primarily use the routing number + account number system instead.
What is the difference between IBAN and SWIFT/BIC?
An IBAN identifies a specific bank account, while a SWIFT/BIC code identifies a specific bank or financial institution. Both are often required for international wire transfers.
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