Luhn 校验器
使用 Luhn 算法校验信用卡号并识别 Visa、Mastercard 或 Amex 等卡组织。
使用方法
How the Luhn check works
Starting from the right, every second digit is doubled and its digits summed. If the total is divisible by ten the number passes. The tool also guesses the network from the leading digits.
- Type or paste the card number.
- The result and card type update as you type.
- Copy the normalised number if needed.
常见问题
Does a passing number mean the card is real?
No. The Luhn check only catches typing mistakes and random numbers. It says nothing about whether the card exists or is active.
Is my card number safe?
Yes, the check happens in your browser and the number is never transmitted.