IBAN Generator and Validator Tool

Introduction

The International Bank Account Number (IBAN) Generator and Validator is a comprehensive tool designed for testing and verification purposes in financial applications, banking software, and educational contexts. This user-friendly application offers two essential features: generating random yet format-compliant IBANs and validating the structural integrity of user-inputted IBANs. Whether you're a developer testing financial software, a QA specialist verifying banking applications, or an educator explaining international banking standards, this tool provides a straightforward solution without requiring complex configurations or third-party integrations.

IBANs (International Bank Account Numbers) are standardized account identifiers used internationally to facilitate cross-border transactions and reduce errors in international money transfers. Each IBAN consists of a country code, check digits, and a basic bank account number (BBAN) that follows country-specific formats. Our tool supports multiple country formats and ensures all generated IBANs pass the MOD 97 validation algorithm specified in the ISO 13616 standard.

How IBANs Work

IBAN Structure and Format

An IBAN consists of up to 34 alphanumeric characters, though the exact length varies by country. The standard structure includes:

Country Code: A two-letter ISO 3166-1 alpha-2 code (e.g., DE for Germany, GB for United Kingdom)
Check Digits: Two digits calculated using the MOD 97 algorithm to validate the IBAN
Basic Bank Account Number (BBAN): Country-specific format that may include:
- Bank code
- Branch code (sort code)
- Account number
- National check digits

For example, a German IBAN follows the structure DE2!n8!n10!n where:

DE is the country code
2!n represents two numeric check digits
8!n represents an eight-digit bank code
10!n represents a ten-digit account number

Different countries have different BBAN formats, resulting in varying IBAN lengths:

Country	Length	Structure	Example
Germany (DE)	22	DE2!n8!n10!n	DE89370400440532013000
UK (GB)	22	GB2!n4!a6!n8!n	GB29NWBK60161331926819
France (FR)	27	FR2!n5!n5!n11!c2!n	FR1420041010050500013M02606
Spain (ES)	24	ES2!n4!n4!n1!n1!n10!n	ES9121000418450200051332
Italy (IT)	27	IT2!n1!a5!n5!n12!c	IT60X0542811101000000123456

IBAN Validation Algorithm

The IBAN validation process uses the MOD 97 algorithm as specified in the ISO 7064 standard. Here's how it works:

Move the first four characters (country code and check digits) to the end of the IBAN
Convert all letters to numbers (A=10, B=11, ..., Z=35)
Calculate the modulo 97 of the resulting number
If the remainder equals 1, the IBAN is valid

Mathematically, this is represented as:

$\text{IBAN number} \bmod 97 = 1$

Our validator implements this algorithm to verify the structural integrity of any IBAN entered by users.

Tool Features

IBAN Generator

The IBAN generator creates random yet valid IBANs for testing purposes. Key features include:

Country Selection: Choose from multiple supported countries including Germany, UK, France, Spain, Italy, Netherlands, Switzerland, Austria, Belgium, and Poland
Format Compliance: All generated IBANs follow country-specific formats and pass the MOD 97 validation
One-Click Generation: Instantly create valid IBANs with a single button click
Copy to Clipboard: Easily copy generated IBANs for use in testing scenarios
Visual Representation: See a color-coded breakdown of the IBAN components (country code, check digits, bank details)

The generator creates IBANs by:

Selecting the appropriate country format
Generating random digits for the BBAN portion
Calculating the correct check digits using the MOD 97 algorithm
Assembling the complete IBAN

IBAN Validator

The IBAN validator checks the structural integrity of user-inputted IBANs. Key features include:

Format Verification: Checks if the IBAN follows the correct country-specific format
MOD 97 Validation: Verifies the check digits using the standard algorithm
Detailed Breakdown: Displays the components of valid IBANs (country code, check digits, bank code, account number)
Error Identification: Provides specific error messages for invalid IBANs
Formatting Assistance: Automatically formats entered IBANs for better readability

The validator performs multiple checks:

Verifies the country code is supported
Checks the IBAN length against country-specific requirements
Validates character types (letters and numbers in correct positions)
Performs the MOD 97 check to verify the check digits

Step-by-Step Guide

Generating an IBAN

Access the Generator Tab: Click on the "Generator" tab (selected by default)
Select a Country: Choose your desired country from the dropdown menu
Generate the IBAN: Click the "Generate IBAN" button
View the Result: The generated IBAN will appear below with a visual breakdown of its components
Copy to Clipboard: Click the "Copy to clipboard" button to copy the IBAN for use elsewhere

Validating an IBAN

Access the Validator Tab: Click on the "Validator" tab
Enter an IBAN: Type or paste an IBAN into the input field
- Spaces and formatting will be automatically handled
- The tool accepts both formatted (with spaces) and unformatted IBANs
View Validation Results: The tool will automatically validate the IBAN as you type
Check the Details: For valid IBANs, a breakdown of the components will be displayed
Review Any Errors: For invalid IBANs, specific error messages will help identify the issue

Use Cases

The IBAN Generator and Validator tool serves multiple purposes across different domains:

Software Development and Testing

API Testing: Generate valid IBANs to test financial APIs without using real account numbers
Form Validation: Test IBAN validation logic in web forms and applications
Edge Case Testing: Verify how applications handle IBANs from different countries
Regression Testing: Ensure IBAN handling remains correct after software updates

Financial Application Development

Payment Systems: Test international payment processing functionality
Banking Software: Verify IBAN parsing and validation components
Fintech Applications: Ensure compliance with international banking standards
Database Systems: Test storage and retrieval of IBAN data

Educational Purposes

Banking Standards Education: Demonstrate how IBANs are structured and validated
Financial Literacy: Teach students about international banking identifiers
Coding Tutorials: Use as an example for validation algorithms and financial data handling
Technical Documentation: Generate example IBANs for API documentation

Data Migration and Conversion

Legacy System Migration: Test IBAN conversion processes when upgrading systems
Data Anonymization: Generate test IBANs to replace real account numbers in development environments
Database Seeding: Create realistic test data for financial application databases

Alternatives

While our IBAN Generator and Validator tool offers a streamlined experience for testing purposes, there are alternative approaches to consider:

Commercial Banking APIs

Pros: Offer additional validation against actual bank registries, provide more comprehensive financial services
Cons: Typically require subscriptions, API keys, and integration work; may have usage limits

IBAN Libraries for Programming Languages

Pros: Can be integrated directly into your codebase, offer programmatic access
Cons: Require development work to implement, may need regular updates to stay current with standards

Official Bank Validators

Pros: Provided by financial institutions, high accuracy for their specific country
Cons: Usually limited to specific countries, may not support generation features

Manual Calculation

Pros: Helps understand the underlying algorithm, no dependencies on external tools
Cons: Time-consuming, prone to human error, impractical for testing at scale

Our tool bridges the gap between these alternatives by providing a simple, accessible interface for both generation and validation without requiring technical integration or paid subscriptions.

Frequently Asked Questions

What is an IBAN?

An IBAN (International Bank Account Number) is a standardized international numbering system developed to identify bank accounts across national borders. It was established by the International Organization for Standardization (ISO) to facilitate error-free international transactions.

How accurate is this IBAN generator?

The IBAN generator creates structurally valid IBANs that pass the MOD 97 check algorithm as specified in the ISO 13616 standard. While the generated IBANs are mathematically valid, they are random and not linked to actual bank accounts, making them perfect for testing but not for real transactions.

Which countries are supported by this tool?

The tool currently supports IBAN formats for Germany, United Kingdom, France, Spain, Italy, Netherlands, Switzerland, Austria, Belgium, and Poland. These cover the most commonly used IBAN formats in Europe.

Can I use generated IBANs for real transactions?

No. The IBANs created by this generator are structurally valid but randomly generated. They are not connected to real bank accounts and should only be used for testing, educational, or demonstration purposes.

How does the IBAN validation work?

The validator checks several aspects of an IBAN:

Country code validity
Correct length for the specified country
Character type validity (letters and numbers in correct positions)
MOD 97 check digit verification according to the ISO standard

Are spaces important in an IBAN?

No. While IBANs are often displayed with spaces for readability (usually in groups of four characters), the spaces are ignored during validation. Our tool handles both formatted and unformatted IBANs.

Is my IBAN data stored or shared when using this tool?

No. This tool operates entirely in your browser. No IBAN data is sent to any server, stored, or shared with third parties. Your data remains private and secure.

Can I validate IBANs from countries not in the dropdown list?

Currently, the tool only validates IBANs from the supported countries listed in the dropdown. If you need validation for additional countries, please let us know through the feedback form.

Why might a valid-looking IBAN fail validation?

An IBAN might fail validation for several reasons:

Incorrect check digits
Wrong length for the specified country
Invalid characters in specific positions
Typos or transposition errors
Country code not supported by the tool

How can I report issues or suggest improvements?

We welcome feedback to improve the tool. Please use the feedback form accessible via the link at the bottom of the page to report any issues or suggest enhancements.

Technical Implementation

For developers interested in implementing IBAN validation and generation in their own applications, here are code examples in various programming languages:

IBAN Validation

1function validateIban(iban) {
2  // Remove spaces and convert to uppercase
3  const cleanedIban = iban.replace(/\s/g, '').toUpperCase();
4  
5  // Check basic format
6  if (!/^[A-Z]{2}[0-9]{2}[A-Z0-9]{1,30}$/.test(cleanedIban)) {
7    return false;
8  }
9  
10  // Rearrange and convert letters to numbers
11  const rearranged = cleanedIban.substring(4) + cleanedIban.substring(0, 4);
12  const converted = rearranged.split('').map(char => {
13    if (/[A-Z]/.test(char)) {
14      return (char.charCodeAt(0) - 55).toString();
15    }
16    return char;
17  }).join('');
18  
19  // Calculate mod 97
20  let remainder = 0;
21  for (let i = 0; i < converted.length; i++) {
22    remainder = (remainder * 10 + parseInt(converted[i], 10)) % 97;
23  }
24  
25  return remainder === 1;
26}
27
28// Example usage
29console.log(validateIban('DE89 3704 0044 0532 0130 00')); // true
30console.log(validateIban('GB29 NWBK 6016 1331 9268 19')); // true
31console.log(validateIban('DE89 3704 0044 0532 0130 01')); // false (invalid check digits)
32

1def validate_iban(iban):
2    # Remove spaces and convert to uppercase
3    iban = iban.replace(' ', '').upper()
4    
5    # Basic format check
6    if not (len(iban) > 4 and iban[:2].isalpha() and iban[2:4].isdigit()):
7        return False
8    
9    # Move first 4 characters to the end
10    rearranged = iban[4:] + iban[:4]
11    
12    # Convert letters to numbers (A=10, B=11, ..., Z=35)
13    converted = ''
14    for char in rearranged:
15        if char.isalpha():
16            converted += str(ord(char) - 55)
17        else:
18            converted += char
19    
20    # Check if mod 97 equals 1
21    return int(converted) % 97 == 1
22
23# Example usage
24print(validate_iban('DE89 3704 0044 0532 0130 00'))  # True
25print(validate_iban('GB29 NWBK 6016 1331 9268 19'))  # True
26print(validate_iban('DE89 3704 0044 0532 0130 01'))  # False (invalid check digits)
27

1public class IbanValidator {
2    public static boolean validateIban(String iban) {
3        // Remove spaces and convert to uppercase
4        String cleanedIban = iban.replaceAll("\\s", "").toUpperCase();
5        
6        // Basic format check
7        if (!cleanedIban.matches("[A-Z]{2}[0-9]{2}[A-Z0-9]{1,30}")) {
8            return false;
9        }
10        
11        // Move first 4 characters to the end
12        String rearranged = cleanedIban.substring(4) + cleanedIban.substring(0, 4);
13        
14        // Convert letters to numbers
15        StringBuilder converted = new StringBuilder();
16        for (char c : rearranged.toCharArray()) {
17            if (Character.isLetter(c)) {
18                converted.append(c - 'A' + 10);
19            } else {
20                converted.append(c);
21            }
22        }
23        
24        // Calculate mod 97
25        BigInteger numeric = new BigInteger(converted.toString());
26        return numeric.mod(BigInteger.valueOf(97)).intValue() == 1;
27    }
28    
29    public static void main(String[] args) {
30        System.out.println(validateIban("DE89 3704 0044 0532 0130 00"));  // true
31        System.out.println(validateIban("GB29 NWBK 6016 1331 9268 19"));  // true
32        System.out.println(validateIban("DE89 3704 0044 0532 0130 01"));  // false
33    }
34}
35

IBAN Generation

1function generateIban(countryCode) {
2  const countryFormats = {
3    'DE': { length: 22, bbanPattern: '8n10n' },
4    'GB': { length: 22, bbanPattern: '4a6n8n' },
5    'FR': { length: 27, bbanPattern: '5n5n11c2n' }
6    // Add more countries as needed
7  };
8  
9  if (!countryFormats[countryCode]) {
10    throw new Error(`Country code ${countryCode} not supported`);
11  }
12  
13  // Generate random BBAN based on country pattern
14  let bban = '';
15  const pattern = countryFormats[countryCode].bbanPattern;
16  let i = 0;
17  
18  while (i < pattern.length) {
19    const count = parseInt(pattern.substring(i + 1), 10);
20    const type = pattern[i];
21    
22    if (type === 'n') {
23      // Generate numeric characters
24      for (let j = 0; j < count; j++) {
25        bban += Math.floor(Math.random() * 10);
26      }
27    } else if (type === 'a') {
28      // Generate alphabetic characters
29      for (let j = 0; j < count; j++) {
30        bban += String.fromCharCode(65 + Math.floor(Math.random() * 26));
31      }
32    } else if (type === 'c') {
33      // Generate alphanumeric characters
34      for (let j = 0; j < count; j++) {
35        const isLetter = Math.random() > 0.5;
36        if (isLetter) {
37          bban += String.fromCharCode(65 + Math.floor(Math.random() * 26));
38        } else {
39          bban += Math.floor(Math.random() * 10);
40        }
41      }
42    }
43    
44    i += 2;
45  }
46  
47  // Calculate check digits
48  const checkDigits = calculateCheckDigits(countryCode, bban);
49  
50  return countryCode + checkDigits + bban;
51}
52
53function calculateCheckDigits(countryCode, bban) {
54  // Create initial IBAN with '00' as check digits
55  const initialIban = countryCode + '00' + bban;
56  
57  // Rearrange and convert letters to numbers
58  const rearranged = bban + countryCode + '00';
59  const converted = rearranged.split('').map(char => {
60    if (/[A-Z]/.test(char)) {
61      return (char.charCodeAt(0) - 55).toString();
62    }
63    return char;
64  }).join('');
65  
66  // Calculate 98 minus mod 97
67  let remainder = 0;
68  for (let i = 0; i < converted.length; i++) {
69    remainder = (remainder * 10 + parseInt(converted[i], 10)) % 97;
70  }
71  
72  const checkDigits = (98 - remainder).toString().padStart(2, '0');
73  return checkDigits;
74}
75
76// Example usage
77console.log(generateIban('DE')); // Generates a valid German IBAN
78console.log(generateIban('GB')); // Generates a valid UK IBAN
79

1import random
2import string
3
4def generate_iban(country_code):
5    country_formats = {
6        'DE': {'length': 22, 'bban_format': '8n10n'},
7        'GB': {'length': 22, 'bban_format': '4a6n8n'},
8        'FR': {'length': 27, 'bban_format': '5n5n11c2n'}
9        # Add more countries as needed
10    }
11    
12    if country_code not in country_formats:
13        raise ValueError(f"Country code {country_code} not supported")
14    
15    # Generate random BBAN based on country format
16    bban = ''
17    format_str = country_formats[country_code]['bban_format']
18    i = 0
19    
20    while i < len(format_str):
21        count = int(''.join(c for c in format_str[i+1:] if c.isdigit()))
22        type_char = format_str[i]
23        
24        if type_char == 'n':  # Numeric
25            bban += ''.join(random.choices(string.digits, k=count))
26        elif type_char == 'a':  # Alphabetic
27            bban += ''.join(random.choices(string.ascii_uppercase, k=count))
28        elif type_char == 'c':  # Alphanumeric
29            bban += ''.join(random.choices(string.ascii_uppercase + string.digits, k=count))
30        
31        i += 1 + len(str(count))
32    
33    # Calculate check digits
34    check_digits = calculate_check_digits(country_code, bban)
35    
36    return country_code + check_digits + bban
37
38def calculate_check_digits(country_code, bban):
39    # Create string for check digit calculation
40    check_string = bban + country_code + '00'
41    
42    # Convert letters to numbers (A=10, B=11, ..., Z=35)
43    numeric = ''
44    for char in check_string:
45        if char.isalpha():
46            numeric += str(ord(char.upper()) - 55)
47        else:
48            numeric += char
49    
50    # Calculate 98 minus mod 97
51    remainder = int(numeric) % 97
52    check_digits = str(98 - remainder).zfill(2)
53    
54    return check_digits
55
56# Example usage
57print(generate_iban('DE'))  # Generates a valid German IBAN
58print(generate_iban('GB'))  # Generates a valid UK IBAN
59

References

ISO 13616-1:2007 - "Financial services - International bank account number (IBAN) - Part 1: Structure of the IBAN"
European Committee for Banking Standards (ECBS) - "IBAN: International Bank Account Number"
SWIFT - "IBAN Registry"
European Payments Council - "IBAN and Creditor Identifier"
Bank for International Settlements - "Payment, clearing and settlement systems"
European Central Bank - "Single Euro Payments Area (SEPA)"
ISO 9362 - "Banking - Banking telecommunication messages - Business identifier code (BIC)"
ISO 7064 - "Information technology - Security techniques - Check character systems"

Conclusion

The IBAN Generator and Validator tool provides a simple yet powerful solution for testing and educational purposes related to international banking identifiers. By offering both generation and validation capabilities in a user-friendly interface, it eliminates the need for complex configurations or third-party integrations.

Whether you're developing financial applications, testing payment systems, or learning about international banking standards, this tool offers a straightforward way to work with IBANs. The comprehensive validation ensures that all generated IBANs are structurally sound and compliant with international standards.

Try generating or validating an IBAN now to experience the tool's capabilities firsthand!

IBAN Generator and Validator Tool for Testing and Verification

IBAN Generator & Validator

Documentation