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US Puzzle Championship - Rules

The official purpose of the championship is to recognize the top U.S. puzzle solvers, and to select members of the U.S. Puzzle Team to participate in the 2010 World Puzzle Championship (Warsaw, Oct. 24-29). Organizers of the Canadian, Italian, and UK teams will use the results in their selection processes. Unofficial participation is open to all puzzlers world-wide. Nationality is determined by citizenship, not residence. All U.S. and international results may be published.


The registration and answer submission pages are new, derived from software originally developed by Logic Masters India. Your answers will go into an active database and will be displayed when you return to the Answer Page after submission, allowing you to visually confirm exactly what was submitted and what the judges will see.


The scoring, bonus, and tie-breaking rules are also new and described below.



All contestants must register to participate in the online championship, and must login to submit answers. Contestants who pre-registered before August 10, will receive email containing their user name and password. Contestants registering starting August 10 will register here and select their own user name and password. See the Privacy Policy regarding our use of registration and other information collected by this site.


Test Procedures

The 2010 Practice Test is available now, using the same formats and procedures as the USPC. You try all of the procedures described here using the Practice Test (including downloading, decryption, printing, answer submission, and answer resubmission).


On Friday, August 20, one day prior to the USPC, you will download the encrypted USPC file to your local computer, and save it until the start time. You can also download the Preview Instructions, containing the USPC puzzle text and any last-minute information.


On Saturday, August 21, at 1pm EDT (Eastern Daylight Time, UTC-4), the USPC will start, and the decryption password (not your login password) will appear on the Password page. Please note: to help reduce network traffic, please refrain from refreshing the password page until the test starting time (use the Timer Window to display a live countdown timer). However, you should test that your web browser will actually refresh the page when requested.


At 3:30pm EDT, the USPC will end. You will have 2 1/2 hours to solve as many puzzles as you can, and submit your answers via the Answer Page. Your submission time is recorded with your answers. After you submit answers you can return to the Answer Page to view your submitted answers, continue solving, and to submit additional answers. It is not necessary to re-submit answers at the deadline if they are already recorded (and doing so would change your time for tie-breaking purposes).



Your last Answer Page submission will be time-stamped and scored. Your final score is the total of all points accumulated, including bonus, minus any penalties.

  • Each correct answer will earn the number of points indicated for the puzzle (which is a rough indication of a puzzle's difficulty). An incorrect answer will incur a penalty of 5 points. Leaving an answer blank will score 0 points. Some puzzles may be open-ended, and any exceptions to scoring will be noted.
  • If you submit all answers correctly, you will receive a bonus of 2.5 points per minute early. (Obviously, bonus points will not affect ranking, but will give a total score that appropriately reflects your finishing the test early.)
  • All answers must be submitted within the 2 1/2 hours time limit. Late submissions will be penalized 10 points per minute after the deadline.


Ranking and tie-breaking will be based on the following rules in order:

  1. Most total points
  2. Earliest submission time


Outside Help

Outside solving help of any kind is not permitted. This includes but is not limited to: assistance of any kind from any other person; prepared notes, books, calculators, computers, or tools other than items explicitly permitted.


You are allowed to use writing implements, eraser, blank paper (including commercial graph paper), ruler, scissors, and tape.



All entries and scores are subject to review for rules compliance. Winners may be asked provide a copy of their passport ID page to prove nationality, and to sign an affidavit confirming that they did, in fact, abide by the rules of the competition. The organizers reserve the right to disqualify any contestant if, in their sole judgment, they believe the rules have been violated.


In case of a dispute, protest, or other judgment, the decision of the judges is final.


Technical Support

The organizers do not expect any technical problems with the operation of championship. If you do encounter a problem that is likely causing trouble for many contestants, check the 2010 USPC home page. If you have a problem that is most likely affecting only you, you may call the test hotline number: 650-302-4898. Officials will not, however, answer any questions regarding the puzzles themselves.


The Results and Winners

The top five U.S. contestants will be notified within two days of the test. Results will be posted on this web site no later than Wednesday, August 25. The answers to the test will be posted no later than one day after the test.


The top three U.S. contestants will be selected for the U.S. Puzzle Team, to compete at the World Puzzle Championship in Warsaw, Poland, October 24-29. The top 25 U.S. contestants will recieve a prize puzzle from ThinkFun.


Unofficial scores for participants from other countries will be posted at the same time as the U.S. scores, and may be forwarded to the corresponding WPC team organizer, upon request, for consideration. If there is no organized team for your country, you may be contacted regarding individual WPC participation.


The top Canadian, Italian and UK contestants: The test results will be sent to the respective WPC team organizers; these results will be used to selection team members.