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Card Payment Form Validator

Check all checkout fields at once: number, expiry, CVC, name and postal code.

Tool inputs stay in your browser · optional AI search sends your query

Good to know: Checks the format only: Luhn checksum, length and the network’s number range. It cannot tell whether a card is real, active or has funds, and nothing is sent anywhere. Use it to compare your own form’s validation rules.

How to use it (step by step)

  1. 1Fill in the boxes: “Card number”, “Expiry (MM/YY)”, “CVC”, “Name on card”, “Postal code”. Example numbers are already there so you can see how it works; replace them with yours.
  2. 2The result updates instantly as you type (on a phone it is below the boxes).
  3. 3The bold line is the main answer. Tap Copy next to any value to copy it.

Words to know

CVV / CVC
The 3-digit code on the back of a card (4 digits on the front for Amex). It proves the person paying has the card in hand.
Expiry date
The month and year printed on a card (MM/YY). The card works until the last day of that month.
Luhn check
A quick math test every real card number passes, like a spelling check for numbers. Passing it only means the number is typed in the right shape, not that the card is real.
Hash / fingerprint (SHA-256)
A short code calculated from a file or text. Change even one letter and the code becomes completely different, so it proves nothing was altered.
Page range
A way to choose pages: 1-3 means pages 1 to 3; 5 means only page 5; 7- means page 7 to the end.

More in Cards & Payments

Idempotency Key GeneratorRandom idempotency keys (UUID v4) to make payment API retries safe.Order / Payment Reference GeneratorUnique-looking order IDs and payment references with your prefix, length and character set.Split Payment Calculator (Exact Cents)Split an amount into equal parts that add up exactly, with leftover cents assigned fairly.Credit Card Interest CalculatorHow much interest a balance costs per day, per month and over a billing cycle at your APR.Credit Card Minimum Payment CalculatorSee how long paying only the minimum takes, and the total interest, versus a fixed payment.APR ↔ Monthly Rate ConverterConvert a credit card APR to monthly and daily rates and effective annual rate, or back.