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Luhn Algorithm Checker

Validate credit card numbers, IMEIs, and other identifiers that rely on the Luhn checksum. Paste a number to see if it passes and generate the required check digit.

Free to use, no watermarks, runs in your browser—nothing uploads to our servers

Number

Formatted

7992 7398 713

Status: Valid

Check digit helper

Add 3 as the final digit to satisfy Luhn.

(New full value: 7992 7398 713)

The Luhn algorithm is designed to catch accidental errors. It does not guarantee that a number is genuine or active — always follow PCI-DSS rules when handling sensitive card data.

Report a bug

If this tool misbehaves, share a quick summary so we can investigate. We include the tool URL automatically—no need to copy and paste.