Card Number Checker (Luhn)
Check card numbers with the Luhn algorithm, detect Visa/Mastercard/Amex brand, and mask for safe display. 100% local.
Card number checker (Luhn)
Runs 100% locally, but prefer test numbers — never paste a real card into any website.
Luhn
Valid ✓
Brand
Visa
Masked
•••• •••• •••• 4242
How to use
- Paste input or drop a file above.
- Adjust options (delimiter, dialect, quality, ratio).
- Copy result or download — no sign-up needed.
FAQ
Should I paste a real card?
No. Use test numbers (e.g. 4242…). Validation is local but real PANs don't belong in browsers.
Does valid mean chargeable?
No. Luhn only catches typos — it says nothing about funds or whether the card exists.