Check a Credit Card Number Free with Our Online Validator
Try Our Free Credit Card Validator
Why Validate Credit Card Numbers?
Before processing payments or testing e-commerce systems, it's crucial to verify that credit card numbers follow proper formatting standards. Our free online validator helps you:
- Prevent payment processing errors by catching invalid numbers early
- Improve user experience with immediate feedback in forms
- Test applications safely without using real card data
- Understand card number structures for different payment networks
How Credit Card Validation Works
The Luhn Algorithm (Mod 10 Check)
Our validator uses the industry-standard Luhn algorithm to verify card numbers. This mathematical check helps detect common errors or fake numbers:
- Starting from the right, double every second digit
- If doubling results in a two-digit number, add the digits together
- Sum all the digits
- If the total modulo 10 equals 0, the number is valid
Example Validation:
Card number: 49927398716
Calculation:
4 9 9 2 7 3 9 8 7 1 6
4×2=8, 9×2=18→1+8=9, 2×2=4, 3×2=6, 8×2=16→1+6=7, 1×2=2
Sum: 8 + 9 + 9 + 4 + 7 + 6 + 9 + 7 + 7 + 2 + 6 = 70
70 ÷ 10 = 7 with 0 remainder → Valid
Learn more about the Luhn algorithm →
Supported Card Types
Visa
- Starts with: 4
- Length: 16 digits
- Example: 4111 1111 1111 1111
Mastercard
- Starts with: 51-55, 2221-2720
- Length: 16 digits
- Example: 5555 5555 5555 4444
American Express
- Starts with: 34, 37
- Length: 15 digits
- Example: 3782 822463 10005
Discover
- Starts with: 6011, 644-649, 65
- Length: 16 digits
- Example: 6011 1111 1111 1117
View complete card type reference →
Frequently Asked Questions
Q: Is this credit card validator safe to use?
A: Absolutely! Our tool runs completely in your browser - we never send your input to any server. The validation happens locally on your device.
Q: Can I validate cards from any country?
A: Yes, our validator works with international credit card numbers from all countries, as long as they follow standard formatting rules.
Q: Does this tool store my credit card information?
A: No. We don't store, log, or transmit any information you enter. The validation occurs entirely within your web browser.
Important Disclaimer
This tool is designed for educational purposes and software testing only. It does not check if a credit card is active or has available funds. Always follow PCI DSS compliance guidelines when handling real payment information.
Ready to Validate Credit Card Numbers?
Our free online validator helps developers, testers, and businesses ensure proper credit card formatting before processing payments.
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