The Credit Card Validator is a free online tool that checks whether a credit card number is valid according to the Luhn algorithm — the standard mathematical formula used by card networks to detect mistyped or invalid card numbers. It also identifies the card type (Visa, Mastercard, Amex, etc.) based on the number prefix.

Luhn validation is the first line of defence against payment form errors — catching typos before a transaction is attempted. This tool is used by developers testing payment forms, analysts verifying card data and QA testers checking input validation.

How to Validate a Card Number

• Enter the credit card number (with or without spaces or dashes)
• Click Validate
• See: card type detected, Luhn check result (valid/invalid) and number formatting

What the Luhn Algorithm Checks

The Luhn algorithm works by doubling every second digit from right to left, summing all digits and checking if the total is divisible by 10. A valid card number always passes this check. Note that passing Luhn validation only confirms the number format is correct — it does not verify the card is real, active or not expired.

For generating test card numbers, use our Credit Card Generator tool. Both are free with no login required.