The Math Club

← The Math Club24 Dec 2025 · 30 min

Partial Credit: Exploring Luhn's Algorithm

Partial Credit: Exploring Luhn's Algorithm24 Dec 202530 min

Ever wonder how a website knows your credit card number is "invalid" before you even hit the submit button? In this commando-style holiday episode, Pete and Noah dive into the secrets of Luhn's Algorithm, a clever approach that uses simple arithmetic to validate sequences of digits.

Leave us a voice message Find us on Twitter

Send us an email

Questions Answered in the Episode:

• How does the Luhn algorithm work to validate credit card numbers?

• Why do credit card companies use a checksum digit?