The Daily Hitori

Today’s board, at whichever size suits the time you have. It is built from today’s date, which is why yours is the same board as everybody else’s.

Puzzle #1 Hard Time 0:00 Decided 0/49

Show mistakesShow the clock

A hard 7×7 board. Tap a cell to paint it out, again to keep it, again to undo.

Check this before you rely on it. This hitori generator is provided free and without warranty, and its results are not professional advice.

Your record

—Current streak
—Longest streak
—Days played
—Best time, this size

The date is the puzzle

Nothing behind this page holds a board of the day and hands it out on request, because there is nothing behind this page. The calendar date becomes a number, that number drives every choice the generator makes, and the same number therefore paints the same pattern and prints the same values on any machine running this code, without coordination and without a request.

It follows that next week’s boards already exist and anyone willing to change their clock can have them. No secret is being kept here and pretending otherwise would be theatre. What you get in exchange is that no past board can ever be lost, which is what makes the archive on this site an archive rather than a collection of links waiting to rot.

The work happens on your own machine, in a background thread, in a few milliseconds. The board printed into this page was built the last time the site was deployed; arrive on a later day and your browser quietly builds that day’s instead, which a generator that is a function of the date can do without asking anybody.

Tuesday is the wall here

Difficulty follows the weekday, read in UTC so everybody turns the page at the same instant. Thursday and Saturday are the gentle days on this board, Tuesday is the hard one, and the rest sit between them.

That shape was chosen against the three other sections rather than copied from any of them. All four ramp from gentle to demanding and all four peak on a different day of the week, so somebody working through the whole site meets one puzzle they can finish and one to grow into on most mornings, instead of four walls arriving together. It is the only editorial coordination between the sections and it costs nothing but the bookkeeping.

Size is an independent choice and does not touch the difficulty. A 10×10 on a Thursday is a hundred cells of comfortable sweeping; a 5×5 on a Tuesday is twenty-five cells and a genuine fight. Choose the size for the time you have and the day for how hard you want to be pushed.

The streak, and what a hint costs you

Finishing any one size records the day. Playing all six does not record six, there is no leaderboard, and the number only says that you turned up — which is the one thing about a person a daily can honestly measure.

A hint names the argument it used and links to the page explaining it, so taking one is the site working rather than you failing. It does not break a streak. It is also not hidden from the share text, which says how many hints you took: a board finished with six hints and one finished with none are different results, and quietly running them together would make the number worthless.

The clock can be switched off completely if being timed spoils the puzzle for you, and the setting is remembered. Your streak, your history and your best time at each size live in this browser’s storage, go nowhere else, and are gone for good if you clear site data for this domain.

Common questions

Is the daily hitori the same board for everyone?

Yes. It is derived from the date rather than delivered from anywhere, and every step of the generator is deterministic, so the same date and size produce an identical board in every browser.

Will taking a hint cost me my streak?

No. Only whether you finished counts. The hint names the argument it applied and links to the page that teaches it, which is the whole reason the button is there.

Why does the daily sometimes take a moment?

Because it is being built rather than fetched. Boards are grown and then judged, and any that needs a guess or has a second answer is discarded, so your browser may build a dozen before one is fit to publish.