WCA Scrambles
The current official scramble programs is TNoodle-WCA-1.2.3. It generates high-quality scramble sequences for all the events of a competition at once.
Download the official scramble program:
TNoodle-WCA-1.2.3Last official change: January 1st, 2026
Important Notes for Delegates
- Official competitions must always use a current version of the official scramble program (see Regulation 4b).
- Delegates should download TNoodle to run it on a computer. They should not use TNoodle running on a public server (for security reasons).
- Delegates must save all scramble sequences generated for an official competition, and send them with the results (see the WCA Competition Requirements Policy).
Scramble Secrecy
- Always encrypt your scrambles in TNoodle with an unguessable password. The password must have nothing to do with the competition or personal data (name, birthdate) of any of the Delegates.
- If you are displaying scrambles on a digital device, only share
[Competition Name] - Computer Display PDFs.zip. - Make sure that only Delegates have access to any other files.
- If you are using a Delegate's computer, use the operating system to create a guest user account and share only the passcode-protected computer display PDFs with it.
- Give passcodes to scramblers when the corresponding groups begin but not any earlier. (In particular, do not give the passcodes for all the scramble sets in a round to scramblers at the beginning of that round.)
- Don't put someone else in charge of the passcodes unless absolutely necessary, and only give them the minimum amount of passcodes needed.
- Additional precautions are outlined in the Scramble Accountability Policy.
Detailed Instructions for TNoodle
TNoodle requires Java to be installed on your computer.
- Run the
https://github.com/thewca/tnoodle/releases/download/v1.2.3/TNoodle-WCA-1.2.3.jar file on your computer.
It will open the page http://localhost:2014/scramble in your browser. - Enter the details for your competition (competition name, number of rounds for each event, details for each round).
If you would like to password protect the file, enter a password. - Wait for the loading bar to finish and click the "Scramble!" button that appears.
A .zip file will download in your browser.
Notes
- 4x4x4 scramble sequences may take a few minutes to initialize and generate. If you are generating 4x4x4 scramble sequences, be patient while the loading bar may appear to be stuck.
- TNoodle creates a
tnoodle_resources folder with a few MB of files (mostly cached tables) in the same folder it is run.
Keep this folder if you want to generate more 4x4x4 scramble sequences more quickly in the future, but feel free to delete it if you need to reclaim disk space. - TNoodle performs scramble filtering according to Regulation 4b3.
About TNoodle
TNoodle uses code developed or adapted by Jeremy Fleischman, Ryan Zheng, Clément Gallet, Shuang Chen, Bruce Norskog, and Lucas Garron. View the TNoodle project on GitHub to view the source, report an issue, or contribute to its development.
History of Official Releases
Old versions must not be used. These are provided in case you want to check the behaviour of an older version.