Daily Shikaku one shared date-stable partition
Daily Shikaku selects one independently verified board from the frozen local source bank for each calendar date. It gives the specialist its own repeatable daily ritual without changing the platform’s frozen Today’s 6 lineup.
Play today’s Daily Shikaku
The date determines the difficulty, source board and symmetry transform. Everyone using the same build and date receives the same board. Your in-progress rectangles, elapsed time and Undo history save locally, so a refresh does not force you to restart.
What is different about the Daily?
Unlimited Practice is seed-based: you can request fresh Easy, Standard or Challenge boards and keep the stabilized URL for replay. Daily mode instead derives its selection from the date. The Daily result is stored in a separate Shikaku history with its own streak and best streak. It does not add Shikaku to Today’s 6 and it does not alter the 2026 six-game rotation hash.
This separation is deliberate. The platform’s main Daily set is a long-lived contract, while specialist Dailies let individual games build a return habit without rewriting that contract every time the catalog grows.
The Daily still uses unique-solution boards
Daily selection does not bypass verification. Each underlying source board first passes the independent exact-cover solver with exactly one legal full partition. The verifier also checks every supported symmetry transform, then replays all 365 date selections for 2026 to confirm deterministic selection and structural validity.
The 2026 schedule intentionally does not claim 365 distinct source-transform starts. Repetition can occur because the frozen bank contains 60 sources and eight transforms per source. The truthful release metric is the actual distinct count reported by the verifier, while every one of the 365 dates is still deterministic and valid.
A Daily Shikaku solving routine
Begin by scanning clue factor pairs. Prime numbers and clues near edges often have the fewest shapes. Next, look at nearby numbers that block one another’s candidate rectangles. Then inspect the live candidate monitor: an open clue with one candidate is forced from the current state and is usually the best next move.
After placing a forced rectangle, scan again instead of immediately moving to the next largest clue. Shikaku deductions cascade because every rectangle consumes cells that other clues might have used. A placement on one side of the board can turn a previously ambiguous clue into a forced one.
Clean and Assisted solves
A Clean solve finishes without Check or Verified Hint. Using either assistance feature marks the run Assisted so local bests do not pretend that a guided solve was unaided. Undo and Redo do not make a run Assisted; they are normal editing tools and are useful when you notice that a rectangle created impossible coverage for a neighboring clue.
The live candidate counts are also not treated as a hidden-answer reveal. They are computed from puzzle rules, clue positions and your already committed rectangles. They are meant to make the deduction state legible, especially on mobile where it is harder to hold many candidate shapes mentally.
Why local autosave matters for a Daily puzzle
A daily game should tolerate interruption. On a phone you may switch apps, lock the screen or reload the page. V0.124 stores the active Shikaku board state in browser-local storage, including committed rectangles, timer state and recent Undo/Redo snapshots. Returning to the same Daily restores the state instead of silently giving you a new board.
When the puzzle is completed, the active autosave is cleared and the result moves into the specialist Daily history. The history records the date, solve time, moves, assistance status and source identifier. All of that stays on the current device; there is no account, remote leaderboard or server-side profile required.
Daily difficulty mix
The schedule mixes Easy 6×6, Standard 8×8 and Challenge 10×10 boards rather than serving the same size every day. Standard is the most common mode because it provides enough space for meaningful candidate interaction without turning a short daily session into a long commitment. Easy dates act as quick warm-ups, while Challenge dates create occasional deeper sessions.
The difficulty label is based on board size and generation constraints, not a claim about intelligence or a diagnostic score. Solve time varies naturally with experience and with the specific geometry of the day’s clues.
Missed the Daily? Practice stays unlimited
The specialist does not need artificial scarcity. If today’s board is finished, or if you prefer another size, unlimited Practice is always available. Fresh Practice seeds let you play new boards immediately, while the Daily preserves the shared date-stable experience and local streak.
That combination supports both search intent and repeat use: someone looking for a Shikaku puzzle can start playing without an account, while a returning player has a clear reason to come back for the date-stable challenge.
Trust contract
The Daily page does not claim global rankings, population percentiles, cognitive diagnosis or a worldwide average solve time because the local-first build does not have evidence for those claims. What it can verify is narrower and more useful: the board is deterministic for the date, the frozen source has one independently counted solution, the runtime needs no paid puzzle service, and local progress can be restored.
That same evidence-first approach applies to the full Shikaku specialist. If a future generator, solver or browser change breaks one of those contracts, release QA is expected to fail rather than quietly weakening the assertion.