Credit Card Number Validator Tool

Validate a credit or debit card number locally using the Luhn check digit and common issuer prefix and length rules. This tool helps catch likely typos and identify likely card brands, but it does not contact any bank, charge anything, or confirm that a card is active or usable.

Financial

Try it

Card number Spaces and dashes are OK

Enter a card number in a single line. The validator ignores spaces and dashes and checks the number locally in your browser.

Privacy note: everything runs locally in your browser. ToolMill does not send card numbers anywhere, and this tool does not perform live issuer, balance, or payment validation.

How it works

Normalizes the input to digits only (spaces and dashes are ignored).
Uses common prefix and length rules to identify likely card brands such as Visa, Mastercard, American Express, and Discover.
Runs the Luhn check digit algorithm to see whether the number is internally consistent.
Does not contact any external payment network or bank.

Examples

Likely valid Visa test number

Input

4111 1111 1111 1111

Output

Likely card type: Visa
Luhn check: valid
Overall result: looks structurally valid

Number with a likely typo

Input

4111 1111 1111 1112

Output

Likely card type: Visa
Luhn check: invalid
Overall result: likely typo or structurally invalid number

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