What is a Credit Card Validator?

A tool that instantly verifies credit card number validity and automatically identifies card types (Visa, MasterCard, American Express, etc.).

It verifies whether entered card numbers are valid according to the Luhn algorithm (the international standard for credit card number verification) and identifies the issuer based on number patterns. Useful for payment system development, testing, and input data validation.

💡 The Luhn Algorithm

The Luhn algorithm (modulus 10 algorithm) is a checksum method used to validate credit card numbers.

1. Starting from the right, double every second digit
2. If doubling results in 10 or more, use the sum of digits (e.g., 12 → 1+2 = 3)
3. Sum all digits
4. If the total is divisible by 10, the card number is valid

This algorithm can detect simple typographical errors but might not detect intentionally falsified numbers.

How to Use

1. Enter a credit card number in the input field
2. The following information will be displayed in real-time
   • Validation result (valid/invalid/incomplete/format error)
   • Card brand (Visa, MasterCard, American Express, etc.)
   • Formatted number display
   • Security code information (CVV/CVC etc.)
   • Valid card length information

You can enter numbers with spaces or hyphens.

4111111111111111
4111 1111 1111 1111
4111-1111-1111-1111

Key Features

• Real-time validation: Results displayed instantly as you type
• Automatic brand identification: Identifies issuer from number pattern
• Luhn algorithm validation: Checks card number validity using international standard
• Format verification: Automatically checks digit count and pattern
• Visual display: Realistic credit card visual display
• Secure design: All processing happens in the browser; no data is sent to any server

Supported Card Brands

This validator can automatically identify the following major credit card brands:

• Visa (VISA): Numbers that start with 4, 13-19 digits (example: 4111111111111111)
• MasterCard (MASTERCARD): Numbers that start with 51-55 or 2221-2720, 16 digits (example: 5555555555554444)
• American Express (AMERICAN_EXPRESS): Numbers that start with 34 or 37, 15 digits (example: 378282246310005)
• Discover (DISCOVER): Numbers that start with 6011, 622126-622925, 644-649, or 65, 16-19 digits (example: 6011111111111117)
• Diners Club (DINERS_CLUB): Numbers that start with 300-305, 36, or 38-39, 14-19 digits
• JCB: Numbers that start with 3528-3589, 16-19 digits (example: 3530111333300000)
• UnionPay (UNIONPAY): Numbers that start with 62, 16-19 digits
• Maestro (MAESTRO): Numbers that start with 5018, 5020, 5038, 5893, 6304, 6759, 6761, 6762, or 6763, 16-19 digits
• Elo (ELO): Card numbers with specific patterns used in Brazil
• Mir (MIR): Cards used in the Russian national payment system
• Hipercard (HIPERCARD): Cards with specific patterns used in Brazil
• Hiper (HIPER): Cards with specific patterns used in Brazil

Use Cases

🛠️ Development & Testing

When developing e-commerce sites or payment systems, verify that various test card numbers are processed correctly.

4111111111111111 → Valid (Visa)
378282246310005 → Valid (American Express)

🔍 Debugging & Problem Solving

When troubleshooting payment errors, quickly check whether the entered card number is structurally correct.

4111-1111-1111-1112 → Invalid (Luhn check failure)

Understanding Validation Results

Valid Card Number

Passes the Luhn algorithm check, matches the required length for the identified card brand, and follows the pattern specifications.

Incomplete Card Number

A card brand can be identified, but the number fails the Luhn algorithm check or has insufficient digits.

Invalid Card Number

Failed the Luhn algorithm check, has an inappropriate length, or the card brand cannot be identified.

Invalid Format

The card number contains characters other than numbers (except spaces and hyphens). Use only numbers, spaces, and hyphens.

Test Card Numbers

Here are test credit card numbers (cannot be used for actual transactions).

Important Notes

⚠️ This tool only checks the structural validity of card numbers. It does not verify if actual cards are valid (expiration date, balance, etc.).

All processing happens in the browser; entered credit card information is never sent to any server.