Credit Card Validator
Test and verify credit card numbers using the mathematical Luhn Algorithm. Perfect for e-commerce developers testing checkout gateways.
How to Use
- Type or paste a credit card number into the large input field above.
- The tool will automatically format the number with spaces as you type, adjusting for specific card formats (e.g., American Express uses a 4-6-5 spacing format).
- Watch the Luhn Validation status instantly tell you if the mathematical checksum of the number is valid.
- The Detected Network status will instantly identify the issuing card brand based on the specific Industry Routing Indicator (IIN) prefix.
Features
Luhn Algorithm
Performs the exact Modulus 10 checksum used by global banks.
Smart Formatting
Auto-formats spaces dynamically based on the detected card type.
BIN / IIN Detection
Identifies Visa, MasterCard, Amex, Discover, Diners Club, and JCB.
Client-Side Processing
Guarantees privacy. Zero API calls or database lookups are made.
What is the Luhn Algorithm?
The Luhn algorithm (also known as the "modulus 10" algorithm) is a simple checksum formula used to validate a variety of identification numbers, such as credit card numbers, IMEI numbers, and National Provider Identifier numbers.
It was created by IBM scientist Hans Peter Luhn in 1954 to protect against accidental errors, such as a user mistyping a digit or swapping two numbers. The algorithm mathematically processes the sequence of digits. If the final resulting sum is divisible by 10, the card number is considered structurally valid.
Note: A "Valid" result in this tool only means the card number mathematically passes the checksum formula. It does not mean the card is currently active, has funds, or is authorized by the issuing bank.
E-Commerce Developer Toolkit
If you are an e-commerce developer testing payment gateways like Stripe or PayPal, you need test cards. You can use our Random Number Generator to create mock CVV codes, the UUID Generator to create fake transaction IDs, and the JSON Formatter to inspect the webhook payloads returned by the payment processor.
Frequently Asked Questions
Does this tool check if my card has money?
No. This tool only performs a mathematical checksum to verify that the string of numbers is correctly formatted. It does not communicate with banks, cannot check balances, and cannot authorize payments.
Is it safe to type my real card number here?
Yes, because the tool runs entirely in your local browser using JavaScript. No data is sent over the internet. However, as a best practice, you should never type your real credit card number into random websites. This tool is primarily designed for developers using test card numbers.
How does it know what network the card is?
Credit card networks use standard prefixes called Issuer Identification Numbers (IIN). For example, all Visa cards start with a 4, and all MasterCards start with numbers between 51-55 or 2221-2720. The tool simply checks the first few digits against these known patterns.
Is it free?
Yes, 100% free with no limits.