Welcome to Codebusters! In this event, participants will cryptanalyze and decode encrypted messages using cryptanalysis techniques for historical and modern advanced ciphers.
The information below should not be interpreted as an extension of the rules. You can find free online copies of the current rules for download on the 2027 Rules page of the Science Olympiad website. The official rules in the current Rules Manual take precedence.
Codebusters Overview (Updated for 2025) - Use this link to access an overview of the Codebusters event containing information about various ciphers as well as instructional resources
Cipher Summary - Use this link to find a breakdown of the Codebusters ciphers by Division & Tournament Type
Codebusters Example Resource Sheet - This document provides teams and coaches with an example of what a Codebusters Resource Sheet could look like at a tournament. It is important to understand that the actual sheet may defer from what is posted here as it should be customized for each tournament by the Event Supervisor.
