Credit Card Validator
Validate card numbers with Luhn checksum, brand detection for Visa and Mastercard, and length checks while keeping every digit local and private offline.
Brand: —
Enter a number
Length: 0
Validation runs locally using the Luhn algorithm. No data is sent anywhere.
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About the author
Written and maintained by the Tool4SaaS team. Every tool runs locally in your browser and is tested in-house for accuracy. Last updated: .
Frequently asked questions
It runs the Luhn checksum and guesses the brand from the prefix.
Yes, it runs locally and stores nothing. Do not enter real card data on random sites.
Yes, it strips spaces and dashes before running the Luhn check, so you can paste numbers with formatting.
How to use Credit Card Validator
- Enter number: Type or paste the card number.
- Read result: See brand, length and validity.
- Check formatting: Review spaces and dashes handling.