IBAN Validator
Validate International Bank Account Numbers (IBAN) with comprehensive checks including country codes, length validation, and mod 97 checksum verification.
Enter IBAN with or without spaces
Test Examples
DE89370400440532013000(Germany - Valid)GB82WEST12345698765432(United Kingdom - Valid)FR1420041010050500013M02606(France - Valid)XX1234567890(Invalid country code)Common IBAN Countries
Reference table showing IBAN lengths for the most common countries
| Code | Country | Length |
|---|---|---|
| DE | Germany | 22 characters |
| GB | United Kingdom | 22 characters |
| FR | France | 27 characters |
| IT | Italy | 27 characters |
| ES | Spain | 24 characters |
| NL | Netherlands | 18 characters |
| BE | Belgium | 16 characters |
| AT | Austria | 20 characters |
| CH | Switzerland | 21 characters |
| PL | Poland | 28 characters |
| SE | Sweden | 24 characters |
| DK | Denmark | 18 characters |
| NO | Norway | 15 characters |
| FI | Finland | 18 characters |
| PT | Portugal | 25 characters |
| IE | Ireland | 22 characters |
| GR | Greece | 27 characters |
| CZ | Czech Republic | 24 characters |
| RO | Romania | 24 characters |
| HU | Hungary | 28 characters |
This validator supports over 80 countries. Full list includes all EU countries and many others worldwide.
How IBAN Validation Works
Country Code Verification
The first two characters must be a valid ISO 3166-1 alpha-2 country code (e.g., DE for Germany, GB for UK).
Length Validation
Each country has a specific IBAN length. For example, Germany requires 22 characters, while France requires 27.
Check Digit Extraction
Characters 3-4 are the check digits (00-99) used for error detection.
Mod 97 Algorithm
Move the first 4 characters to the end, replace letters with numbers (A=10, B=11, ..., Z=35), then calculate mod 97. A valid IBAN equals 1.
Country-Specific
Validates against specific length requirements for 80+ countries.
Mod 97 Check
Verifies checksum using the official mod 97 algorithm.
Auto-Formatting
Formats IBAN with spaces every 4 characters for readability.
Frequently Asked Questions
What is an IBAN?
IBAN (International Bank Account Number) is an internationally agreed system of identifying bank accounts across national borders. It consists of a country code, check digits, and a country-specific bank account number.
How does IBAN validation work?
IBAN validation checks three things: 1) Country code is valid, 2) Length matches the country's specification, and 3) Check digits pass the mod 97 algorithm verification. The mod 97 algorithm moves the first 4 characters to the end, converts letters to numbers (A=10, B=11, etc.), and verifies the result modulo 97 equals 1.
What is the mod 97 algorithm?
The mod 97 algorithm is used to validate IBAN check digits. It rearranges the IBAN by moving the first 4 characters to the end, replaces each letter with its numeric equivalent (A=10, B=11, ..., Z=35), and calculates the modulo 97. A valid IBAN produces a result of 1.
How many characters should an IBAN have?
IBAN length varies by country. For example, Germany (DE) has 22 characters, UK (GB) has 22, France (FR) has 27, Italy (IT) has 27, Spain (ES) has 24, and Netherlands (NL) has 18. The validator checks that your IBAN matches the expected length for its country.
Can I validate IBANs from any country?
This validator supports over 80 countries that use IBAN, including all EU countries and many others worldwide. Each country has specific length requirements and formatting rules that are checked during validation.
What do the check digits do?
The check digits (positions 3-4) are calculated using the mod 97 algorithm and are used to detect errors in the IBAN. They ensure that typos or transcription errors can be caught. Our validator verifies these check digits are correct.