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CVV / CVC Format Checker

Check a security code has the right length for the card brand (3 or 4 digits).

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

Good to know: Format check only; the real CVV can only be verified by the card issuer.

How to use it (step by step)

  1. 1Fill in the boxes: “Brand”, “Security 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.

More in Cards & Payments

Chargeback Ratio CalculatorYour dispute/chargeback ratio and how many more you can have before hitting a threshold.Payment Approval Rate CalculatorAuthorization approval and decline rates, and revenue lost to declines.Refund Cost CalculatorWhat a refund costs you when the original card fee is not returned.Card Minimum Purchase CalculatorThe smallest sale where the card fee stays under your chosen percentage.Dynamic Currency Conversion (DCC) Markup CalculatorPay in local or home currency? See the hidden markup in the rate you were offered abroad.Payout / Settlement CalculatorNet payout from gross card sales after fees, refunds, chargebacks and a reserve.