Credit Card Validator: Check Card Number Candidates You Already Have
The Credit Card Validator checks one candidate or a pasted list for allowed characters, a 12-19 digit length, a built-in known network prefix, and the Luhn checksum. It removes spaces and hyphens before checking. Numeric results longer than four digits show only their last four digits; inputs of four or fewer digits are fully masked, while inputs with invalid characters show no masked number. A valid format result is structural only; it does not confirm that a number is issued, active, funded, owned, or authorized.
How to Use the Validator
- Pick a mode: Single Candidate for one number, or Bulk Candidates for a list.
- In Single Candidate mode, type or paste a value; validation updates automatically.
- In Bulk Candidates mode, paste candidates into the text area. Separate them with line breaks, commas, or both; empty entries are ignored.
- In Bulk Candidates mode, validation updates automatically as the list changes.
- Review the status, network, digit count, and applicable reasons for each candidate.
Understand the Results
Spaces and hyphens are removed before checking. Other characters cause the allowed-characters check to fail. The core Valid format status requires allowed characters, 12-19 digits, and a passing Luhn checksum.
Single results show the masked number, digit count, allowed characters, length range, detected network, network-length match, and Luhn checksum. Bulk results show Masked Number, Network, Digits, Status, and Reasons.
- Network detection and network-length matching are informational checks. They do not decide the status by themselves.
- A known prefix with an unexpected length can add a reason while the result still shows Valid format if the core validity checks pass.
- Unknown means no built-in known prefix matched. Length and Luhn checks can still run.
- Empty input or invalid characters can stop later checks from being calculated.
- Numeric inputs longer than four digits show only their last four digits. Inputs of four or fewer digits are fully masked; inputs with invalid characters show no masked number.
Copy or Download Bulk Results
After bulk validation, click Copy CSV or Download CSV. The CSV includes Masked Number, Network, Digit Count, Length OK, Luhn OK, Status, and Reasons. It uses masked values rather than full candidates.
Limitations and Data Handling
This tool performs structural checks in the browser. It does not contact a card network, issuer, or payment processor, perform payment authorization, or verify whether a number is real, active, funded, issued, owned, or authorized. Network support uses built-in known prefix patterns and is informational, not exhaustive.
The input fields display pasted candidates unmasked. Masking applies to results and CSV output, so clear the input fields yourself when finished. There is no file-upload or import control.
Frequently Asked Questions (FAQs)
Does a "Valid format" result mean the card is real, active, or funded?
No. This tool checks structure only - allowed characters, length, built-in network patterns, and the Luhn checksum. It does not claim that a number is issued, active, funded, or owned by any person, and performs no payment authorization or network call.
How is this different from a credit card extractor?
An extractor searches arbitrary text for card-number-shaped patterns. This validator checks specific candidates you supply directly - one or many - against the same structural rules.
Is it safe to paste real card numbers into this tool?
The page states that processing happens locally in your browser. Still, treat real cardholder data carefully: input fields show pasted candidates unmasked, while results are masked. Clear the input when done and follow your organization's data-handling policies.
What card networks are supported?
Built-in known prefix patterns cover Visa, Mastercard, American Express, Discover, Diners Club, JCB, UnionPay, and Maestro. Support is informational and not exhaustive. Anything outside those patterns is labeled Unknown but can still be checked for length and Luhn validity.
Does bulk mode accept comma-separated lists?
Yes. Bulk input accepts candidates one per line, comma-separated on a single line, or a mix of both. Empty entries are ignored.