Skip to main content
Tool Factory

Cryptography & Ciphers

Colossus Cipher Processor

Apply Colossus with explicit key, format, and algorithm settings. Enter the data and key material, choose the parameters, then review the result.

Tool workspace

Your input stays in this browser.

Add the required input to continue.

Needs input

You can run the tool again after any change.

Options

Your result appears here

Apply Colossus with explicit key, format, and algorithm settings. Enter the data and key material, choose the parameters, then review the result.

This tool runs open-source code from CyberChef by GCHQ (Apache License 2.0). See open-source credits.

Colossus Cipher Processor uses Lorenz statistical wheel analysis to process the supplied input. It reports counters and wheel-position results for the selected Lorenz analysis program, not an Enigma rotor search.

It reports counters and wheel-position results for the selected Lorenz analysis program, not an Enigma rotor search. Processing runs in the browser for this catalog category, so the result depends on the supplied bytes and settings. Processing runs in the browser.

Cipher search explores the configured space; it does not bypass strong encryption or establish evidence authenticity.

Instructions

  1. Provide text or data for this tool.
  2. Start with a short valid ITA2 fixture and Letter Count. This applies to Colossus Cipher Processor.
  3. Record the pattern, counters, and wheel starts before comparing a second run. This applies to Colossus Cipher Processor.

Example

Input: Use a public ITA2 test sequence, KH Pattern, and Program to run: Letter Count.

Settings: Colossus Cipher Processor: Select Program exposes predefined analyses; advanced K Rack controls configure counting logic. Fast Step, Slow Step, and wheel starts define the search positions.

Result: It reports counters and wheel-position results for the selected Lorenz analysis program, not an Enigma rotor search. Processing runs in the browser for this catalog category, so the result depends on the supplied bytes and settings.

Limits

  • Colossus Cipher Processor: An arbitrary plaintext string is not necessarily valid ITA2 input.
  • Colossus Cipher Processor: Statistical counter results require interpretation and do not automatically recover the original plaintext.

Questions

What input does Colossus Cipher Processor accept?

Colossus Cipher Processor accepts text. Colossus is the name of the world's first electronic computer. Ten Colossi were designed by Tommy Flowers and built at the Post Office Research Labs at Dollis Hill in 1943 during World War 2. They assisted with the breaking of the German Lorenz cipher attachment, a machine created to encipher communications between Hitler and his generals on the front lines. To learn more, Virtual Colossus, an online, browser based simulation of a Colossus computer is available at virtualcolossus.co.uk. A more detailed description of this operation can be found here.

Which settings does Colossus Cipher Processor provide?

Colossus Cipher Processor provides controls for Input, Pattern, QBusZ, QBusΧ, QBusΨ, Limitation, K Rack Option, Select Program, Top Section - Conditional, Bottom Section - Addition, Advanced, Program to run, K Rack: Conditional, R1-Q1, R1-Q2, R1-Q3, R1-Q4, R1-Q5, R1-Negate, R1-Counter, R2-Q1, R2-Q2, R2-Q3, R2-Q4, R2-Q5, R2-Negate, R2-Counter, R3-Q1, R3-Q2, R3-Q3, R3-Q4, R3-Q5, R3-Negate, R3-Counter, Negate All, K Rack: Addition, Add-Q1, Add-Q2, Add-Q3, Add-Q4, Add-Q5, Add-Equals, Add-Counter1, Add Negate All, Total Motor, Master Control Panel, Set Total, Fast Step, Slow Step, Start Χ1, Start Χ2, Start Χ3, Start Χ4, Start Χ5, Start M61, Start M37, Start Ψ1, Start Ψ2, Start Ψ3, Start Ψ4, Start Ψ5.

What does Colossus Cipher Processor return?

Colossus Cipher Processor returns a structured JSON value.