Credit Card Number Validator

Credit Card Number Validator checks whether card numbers are correctly formed, one at a time or in bulk. For each line it checks the allowed characters, normalises spaces and hyphens, verifies the length and the Luhn checksum, and identifies the likely network from published static prefix ranges. Results, copies and reports only ever show masked numbers, and nothing is sent or stored.

Typing mistakes in card numbers cause failed payments and support requests. Checking the format first — for example when testing a checkout form or cleaning test data — catches mistyped or swapped digits instantly. Because the check is purely mathematical and local, no payment system or card data service is involved.

1. Paste card numbers, one per line, or press Load test numbers.
2. Press Validate.
3. Review the counts and the masked results table.
4. Use the Show filter to focus on invalid entries or duplicates.
5. Copy the masked valid or invalid results, or download a CSV or TXT report.
6. Press Reset to clear everything.

• Bulk checking with one number per line
• Allowed-character check with space and hyphen normalisation
• Length check (12–19 digits) and network-specific lengths
• Luhn checksum verification
• Likely network from static prefix ranges
• Masked numbers only in results, copies and reports
• Valid, invalid, duplicate and empty-line counts
• No CVV, expiry, name or other payment details requested

• Use published test numbers when testing payment forms.
• Never paste real card numbers into tools or documents you don’t control.
• Treat a passing result as a format check only — the issuer must authorise any payment.
• Clear the tool with Reset after use, especially on shared computers.
• Check the reason given for each invalid line to find typing mistakes.