Credit CardValidator
Validate credit card numbers using the industry-standard Luhn algorithm. Instantly check card validity and identify card brands for testing and development purposes.
Important Security Notice
This tool only validates the format and checksum of credit card numbers. It does not verify if the card is real, active, or usable for transactions. All validation happens locally in your browser for maximum privacy.
Credit Card Validator
Enter a credit card number to validate it using the Luhn algorithm
Credit Card Validator
Enter a credit card number to validate it using the Luhn algorithm and identify the card brand.
What is Credit Card Validation?
Credit card validation is the process of checking if a credit card number follows the correct format and mathematical rules, without verifying if the card is real or active.
Format Validation
Checks if the card number has the correct length and starts with the right digits for its brand.
- • Visa: 16 digits, starts with 4
- • Mastercard: 16 digits, starts with 51-55
- • Amex: 15 digits, starts with 34 or 37
Luhn Algorithm
A mathematical formula that calculates a checksum to detect simple errors in card numbers.
- • Catches 100% of single-digit errors
- • Detects 90% of digit transposition errors
- • Industry standard since 1954
How to Use the Validator
Validate any credit card number in just three simple steps
Enter Card Number
Type or paste a credit card number into the input field. Spaces and formatting will be added automatically for better readability.
Click Validate
Press the validate button to run the Luhn algorithm check and automatic brand detection on your card number.
View Results
See instant validation results including validity status, card brand, length, and detailed Luhn check information.
Understanding the Luhn Algorithm
The Luhn algorithm, also known as the "modulus 10" algorithm, is a simple checksum formula used to validate credit card numbers, IMEI numbers, and other identification numbers. It was created by IBM researcher Hans Peter Luhn in 1954.
How the Algorithm Works:
- Starting from the rightmost digit (excluding the check digit), double every second digit
- If doubling results in a two-digit number, add the digits together (e.g., 16 becomes 1+6=7)
- Sum all the digits in the card number
- If the total sum is divisible by 10, the number is valid according to the Luhn algorithm
Example: Validating 4532015112830366
The Luhn algorithm is designed to catch common errors in credit card numbers, including:
- Single digit errors (changing one digit)
- Most adjacent digit transposition errors (swapping two adjacent digits)
- Other common transcription errors
Note: The Luhn algorithm only validates the mathematical correctness of a card number. It does not verify if the card exists, is active, or has sufficient funds. Actual card verification requires authorization from the issuing bank.
Supported Card Brands
VVisa
The world's largest payment network
- • Starts with: 4
- • Length: 16 digits
- • Founded: 1976
MCMastercard
Global payment technology company
- • Starts with: 51-55
- • Length: 16 digits
- • Founded: 1966
AEAmerican Express
Premium payment and travel services
- • Starts with: 34, 37
- • Length: 15 digits
- • Founded: 1850
DDiscover
Digital payment services
- • Starts with: 6011, 622, 64, 65
- • Length: 16 digits
- • Founded: 1985
JCBJCB
Japan's international payment brand
- • Starts with: 35
- • Length: 16 digits
- • Founded: 1961
DCDiners Club
Premium charge card company
- • Starts with: 30, 36, 38
- • Length: 14 digits
- • Founded: 1950