Credit card validator
Check a card number with the Luhn algorithm and see its network. Format check only, free, and nothing leaves your device.
The result will appear here.Related tools
Everything you need to check a card number
Instant check
The result updates as you type, with no button to click.
Luhn checksum
Runs the same checksum that card issuers build into every number.
Network detection
Names the card network from the leading digits and length.
Forgiving input
Spaces and dashes are ignored, so you can paste a number as printed.
Clear digit count
See the number in readable groups, with its digit count.
100% private
Runs entirely in your browser. Nothing is uploaded or stored.
Check a card number in three steps
- 1
Enter the card number
Type or paste the number. Spaces and dashes are fine, they are ignored for you.
- 2
Read the result
You see at once whether the number passes the Luhn check, how many digits it has and which card network it matches.
- 3
Fix typos or move on
If the check fails, look for a mistyped or swapped digit. If it passes and a network is named, the number is correctly formatted.
Built for developers and testers
A card number carries a built-in checksum. PixelTools runs it instantly so you can catch typos and test your forms, with no upload and no account needed.
Testing checkout forms
Confirm a test number passes before you use it to try a payment form.
Checking your own validation code
Compare your Luhn implementation against a known-good result.
Spotting typos
Find out whether a number copied from a document or email was mistyped.
Learning how card numbers work
See how length, leading digits and a checksum shape every card number.
Frequently asked questions
What does a credit card validator check?
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It runs the Luhn checksum and then checks the prefix and length against known card networks. A number is called valid only when both agree. This catches typos, such as a mistyped or swapped digit.
Does it tell me if a card is real or has funds?
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No. Passing the check only means the number is mathematically plausible. It does not confirm the card exists, is active, or has money on it. Only the card issuer or a payment processor can do that.
What is the Luhn algorithm?
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The Luhn algorithm is a simple checksum used by card numbers. Starting from the second digit from the right, every other digit is doubled, the digits are summed, and the total must be divisible by 10. It was designed to catch accidental typing errors, not to stop fraud.
Is it safe to enter a real card number?
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The check runs entirely in your browser and nothing is uploaded or stored. Even so, you do not need a real card here. For testing, use the public test numbers that payment providers publish.
Which card networks are recognized?
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Visa, Mastercard, American Express, Discover, JCB, Diners Club, UnionPay and Maestro, based on the leading digits and the length of the number.
Why does a valid-looking number fail?
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A single wrong or swapped digit breaks the checksum. Re-check the number against the card, and make sure no letters or extra characters were pasted in.
Try the credit card validator now
Free, no account needed.