Frequently asked questions

Create an account, then open a contest from the contest list. Running and upcoming contests are at the top. On the contest page, read the instruction booklet, then press Start when you are ready.

Most contests are open for several days. You can start any time in that window, up to the latest start time on the contest page. Times are in Indian Standard Time (IST).

Once you start, your timer runs for the contest's length and can't be paused, even if you close the page.

LMI doesn't recommend one. Choose what suits you: a printer, the puzzle types, the grid sizes. In contests with online solving you pick one when you start, and you can switch at any time, even puzzle by puzzle. The contest page remembers your choice for next time.

• Paper solving: print the puzzle booklet (its password is shown when you start), solve on paper, then type each puzzle's answer key on the contest page.
• Online solving: solve each puzzle in Penpa on the contest page and submit the answer key below the grid.

A short code from your solved grid, usually the contents of one or two marked rows or columns. The instruction booklet says what to enter for each puzzle. Without instant grading, a key in the wrong format can be marked wrong, so check it against the booklet's example.

Your timer keeps running. Answers you have submitted are saved on the server. Answers you typed but didn't submit yet are kept in your browser, so they're still there after a reload on the same device. In online solving, your marks in a Penpa grid are not saved, so submit each puzzle before you move on.

Yes, most contests from 2021 on can be played unofficially. In the contest list they're marked "Play unofficially". You get the full timer and your answers are checked, but the result doesn't count for ratings, and on the score page you're marked Unofficial.

Contests for players who are new to LMI. Everyone may play, but newcomers are ranked first on the score page, with their overall rank beside them, and the contest list shows the best newcomers. A newcomer is anyone with a score above zero in at most one LMI contest before that one.

Choose a puzzle from the list, solve it in the Penpa grid, then type the answer key in the boxes below the grid and press Submit. Answers are not submitted by themselves, so submit each puzzle before you switch to another.

Read the short guide to Penpa. A more detailed one is on the Penpa home page. Trying a past contest unofficially is a good way to practise.

Choose the puzzle again from the list to reload it. On a phone, turning it sideways gives the grid more room. Penpa works best with a mouse or a keyboard.

The latest versions of Google Chrome, Microsoft Edge and Opera. Firefox is not supported for online solving.

In contests marked "Instant grading", each answer is checked as soon as you submit it, and you can try again if it's wrong (the booklet says whether wrong answers cost points). Without instant grading, answers are only saved. You can change them until your time is up, and you see your results on the score page after the contest.

If you solve every puzzle correctly, many contests give bonus points for each minute you have left. The booklet gives the points per minute.

• With instant grading, your time stops at your last correct answer.
• Without instant grading, it stops when you press Claim bonus. If you don't, you get the full contest length and no bonus.

On the score page, "All solved · 54:16" is the time a player took to finish.

The ranking, with points, puzzles solved and finish times. Tap a player to see each puzzle. "New" marks players who finished since your last look, and "Solving" those still on the clock. The Puzzles tab has each puzzle's statistics and solutions once the contest is over, and your own answers.

Most monthly Puzzle and Sudoku contests do, when you take part in the official period. The contest page says so before you start, and some contests let you choose. Ratings are updated after the contest, once the results are final. Unofficial play doesn't count.

On the score page, open the Puzzles tab: your wrong answers have a Claim button. Explain what happened, for example a typo in the key or a different reading of the rules. The organisers decide, and the bell at the top lets you know. With instant grading, an accepted claim removes the penalty for that wrong answer; without it, your answer counts as correct. Your score changes straight away.

Only you and the contest's organisers. It's a private thread in the discussion, so you can reply there if they ask you something.

Every contest page has its own discussion. Before you finish you can ask about the rules, and the organisers read it. Afterwards, "How did it go?" is for sharing how it went and asking about puzzles. On the score page, "Discuss this puzzle" shows only the posts about that puzzle.

Select the text and press Spoiler, or type it ||like this||. It stays hidden until someone taps it. Please hide anything that gives away a solution while the contest is still running.

Type @ and choose from the list. A puzzle mention like @#6 shows the puzzle's name and links to its posts; a player mention lets that player know through the bell. Replying to a reply mentions its author for you.

Yes, tick "Post anonymously". Other players won't see your name; the moderators still can. Announcements and replies in a claim can't be anonymous.

When you have finished, "Rate this contest" asks for 1 to 5 stars, and you can pick up to 3 favourite puzzles. "Share in the discussion" puts your favourites in a message, so you can say why you liked them. Once the contest is over, everyone's ratings and favourites appear on the score page.

Use Forgot your password? with your username or email. We email you a link to choose a new one. It works once, for 60 minutes.

Log in and open your settings. Your name is optional; without one, your username is shown. Your email is never shown to other players.

Every player has a page with their contests, newest first, wins and podiums, and ratings. Tap a player's name on a score page or in the contest list, or go to /players/ followed by the username.