Changelog

Version history

1. 0.3.122026-10-20
   • ChangedWhere the app would show an ad, the game now shows the Play Sudoku page on Google Play instead. The one for hints gives you the hint after 3 seconds, as in the app
   • ChangedThe ad space on the difficulty pages now holds a Google Play link to the Play Sudoku app
   • ChangedThe Google Play button is now Google's official badge, in the page's language
2. 0.3.112026-10-20
   • AddedThe game on the home page is now the same game as the Play Sudoku app for Android. Boards you were solving and shared links still open on the difficulty pages (/easy …)
3. 0.3.102026-10-19
   • ChangedThe privacy policy now covers the Play Sudoku app for Android: Google AdMob ads, the Remove ads purchase and usage statistics. The web game here has no app ads and works as before
4. 0.3.92026-09-24
   • AddedEach level now has its own address. Open /expert and an expert puzzle starts right away, with the techniques that level adds listed below
   • AddedTwo new guides: how the levels are graded, with figures measured on 60 puzzles per level, and when and how to write notes
   • ChangedArriving through a level address keeps the puzzle you were solving. Only a puzzle you haven't touched is swapped for one at that level
   • ChangedThe typeface is now Onest. Digits come out almost exactly as tall and wide as on the sudoku.com grid
5. 0.3.82026-09-16
   • ChangedThe on-screen wording and the hint sentences are shorter and plainer, and the pages now use the same words the buttons do
   • ChangedThe daily, tournament and awards pages are about half as long. The streak rule, how scores add up and what earns a medal are all still there
   • FixedThe about page said there were no leaderboards and that hints are never rationed. The tournament has standings, and you get three hints per game
   • FixedThe tournament description only said you race a field of 100. It now says the other 99 players are simulated
   • FixedWhen your hints ran out, the game told you to start a new game or restart. It now points at “With the coach”, which keeps the puzzle you are on
6. 0.3.72026-09-13
   • AddedEntering a number or note now makes a short sound. You can turn it off and back on in Settings
   • FixedThe Q shortcut for Quick entry now works: press Q, pick a digit, then press Enter to place it
7. 0.3.62026-09-13
   • FixedWhen the hint got stuck it told you to press Check — there is no Check button. It now says to clear the wrong numbers first
   • FixedThe tournament runs for a month, but the line at the end called it this week's
   • FixedNaked pair and triple hints named the row twice: r5c2 and r5c4 already say row 5. Seven lines in ten read that way
   • ChangedWhen the hint runs out of ideas it no longer lists all thirteen technique names. The names live on the How to solve page
   • ChangedHow to solve is now in the top bar. The only way in to the thirteen techniques used to be one line at the foot of the page
8. 0.3.52026-09-12
   • AddedThere is a With the coach mode now. Hints without a limit, and three mistakes no longer end the game — it is a place to learn the techniques
   • AddedRun out of hints and a With the coach button appears right there. It keeps the puzzle you are on and lifts the limit
   • AddedSettings now has a Dark screen switch. It darkens the board and the whole page, and carries over to the other pages
   • AddedFilling a row, column, or box with 1 through 9 now makes those nine cells pop in turn. A unit with a repeated digit stays still
   • AddedFinishing a puzzle now names the badge you just earned, right there. You no longer have to open the awards page to find out
   • ChangedThe finished grid now gets 0.6 seconds of its own before the result window opens — a ripple spreads from the cell you filled last
   • ChangedThe result window now shows what this game added: how many you have solved, and how many days you are on
   • ChangedThe result window now also shows the points you have piled up this month. The number above is this puzzle; the line below is everything added up
   • AddedFourteen badges became twenty-one. Twenty-five, two hundred and five hundred puzzles, plus a two-week streak, so the next rung is closer
   • AddedThree badges now come from points earned. Points grow faster on harder levels, so it is a different path from the puzzle-count badges
   • ChangedThe main button on the result window is now Play again. It opens the next puzzle at the same level straight away, with no second pick
   • ChangedThe dark colours were measured, not guessed. The tightest pair — an entered number on the selected cell — sits at 5.09:1
   • ChangedThe next puzzle is now built while you solve. Play again opens instantly, even on Very hard, with no waiting screen
   • AddedFinishing a puzzle now remembers which technique decided it. The How to play page shows how many of the thirteen you have met, and which one comes next
   • AddedOne more badge, twenty-two now. It lights up when you have met all thirteen techniques — the practice puzzles on each technique page are the way there
   • ChangedThe board diagrams on the technique pages follow the dark screen too. The dimmed cells and the highlighted line got their own dark colours
   • AddedThe technique pages now say where you are too — whether you have met this one, or how many of the thirteen you have met so far
   • FixedFixed the run-together text at the top of the technique pages: it read difficultyHard instead of difficulty Hard
   • ChangedA coached game is kept out of your records, score and tournament. A time set with unlimited help would not mean anything
9. 0.3.42026-09-12
   • AddedThere is a contact page now. The link at the bottom of every page opens it, and leaving an address gets you an answer
   • ChangedThe contact form moved out of the about page and onto its own. You no longer scroll past the essay to reach it
10. 0.3.32026-09-11
    • ChangedA pasted link now shows the board rather than the name — one box lit, and inside it only one cell where the 8 can go
    • FixedThe tab icon was blank in Safari and could not appear in Google results — Google does not accept SVG icons
11. 0.3.22026-09-09
    • ChangedThree blocks came off the front page: the one about hints, the list of features, and the one about difficulty. What sits under the board is a third of what it was, and the hint and difficulty explanations are still on the how-to-play and about pages
    • ChangedDropped the paragraph about the record living in this browser from the awards, daily and tournament pages. The same thing was said on all three, and none of it helps while you are playing
    • AddedYou can add this to your home screen now. The tab icon was also still magenta from an older palette; it matches the site again
    • AddedA line above the board now shows your best time at this level and your run of days. On a phone the records table sits off-screen, so you never saw it until you finished
    • AddedA link you share now shows your time as a picture. It used to be the same image whichever puzzle you solved
    • FixedThe clock starts when you first touch the board. It used to run while you were still reading, so new times may look faster than your old ones
    • AddedOpen a link a friend sent and their time comes with it. When you finish, the two times sit side by side
    • AddedA link you share now unfurls in chat with the level and your time on it. Opening it drops the other person straight onto that board
    • AddedThe window that appears when you solve a puzzle can now share the result. On a phone it opens the system share sheet; otherwise the line and the link are copied
    • AddedPaste a link to this site into a chat or a post and it now shows a picture of a grid. It used to be text only
    • ChangedThe first screen paints sooner. Pages that are not in Korean were pulling down 282 pieces of a Korean webfont before anything could be drawn; now only the Korean pages do
    • FixedThe site name sits at the far left again. On narrow screens the menu button had been pushing it out of place
    • FixedThe menu button has a bigger area to hit. The icon looks the same, but the target went from 22px to 44px, so it is harder to miss with a thumb
12. 0.3.12026-09-07
    • FixedFixed a case where finishing after midnight, with the tab left open, was counted as today. The board in your hands is yesterday's, so it no longer extends the run.
    • FixedFixed the game page scrolling sideways on a phone. Invisible tooltips were still taking up space.
    • ChangedPages got a little lighter. Developer comments that never showed on screen were being shipped with them.
13. 0.3.02026-09-06
    • Rule changeEvery puzzle is now checked at build time to be solvable by logic to the last cell, and only those go out. Four out of five expert boards used to leave you guessing partway
    • ChangedA puzzle number opens a different board than before, because the way boards are built changed
    • AddedA progress bar appears while a board is being built. It shows up only when the search runs long, and says how many boards have been checked
    • FixedThe screen no longer freezes while a board is built. You can pick another difficulty mid-search
    • ChangedMuted text is darker. Labels, the status line and notes went from 4.1:1 contrast to 5.1:1
    • FixedThe “OFF” pill on the notes button is readable. White on grey measured 2.05:1
    • ChangedThe count of remaining digits moved below the number, not beside it. On phones the small “5” next to “1” read as 15
    • ChangedBoard digits are slightly larger, matched by measuring letter heights against the site we compare with
    • ChangedMistakes, time and the buttons split the row above the board into equal thirds. The clock and the buttons used to sit on top of each other
    • ChangedThe site is called Play Sudoku, at play-sudoku.co
    • FixedAbout, privacy, terms and the changelog now exist in each language. Following them from the English pages no longer drops you into Korean
    • AddedTraffic measurement is on. It records which pages were viewed; the board you are solving and your time are never sent
    • AddedA solver arrived. Type in the board you are stuck on and it hands you one step at a time, each with the reason
    • AddedA printable page arrived. Up to six boards at once, each carrying its number so you can reopen it here when paper runs out of help
    • ChangedAn inquiry is now kept as a post only the operator can read. It used to try to send mail, and without the setup it went nowhere
    • AddedGerman arrived — the hint sentences too, not just the buttons: “Im Block oben Mitte kann die 3 nur in r3c5 stehen”
    • ChangedThe language picker is a dropdown now. With eighteen languages planned, a row of names would fill the footer
    • AddedSpanish arrived — the hint sentences too: “En el bloque superior central, el 3 solo puede ir en r3c5”
    • AddedThe awards page now lists your months. Each one shows how many daily puzzles you finished, and months you skipped stay on the shelf as empty cards
    • AddedFinish the daily puzzle on every day of a month and that month gets a trophy
    • AddedFinished tournaments now carry a medal — gold for the top 10%, silver for 25%, bronze for 50%
    • ChangedThere are fourteen badges now. A full month and Medallist joined the list
    • AddedFrench arrived — the hint sentences too: “Dans le bloc en haut au centre, le 3 ne peut aller qu'en r3c5”
    • AddedItalian arrived — the hint sentences too: “Nel blocco in alto al centro, il 3 può andare solo in r3c5”
    • AddedPortuguese arrived — the hint sentences too: “No bloco superior central, o 3 só pode ir para r3c5”
    • AddedSimplified Chinese arrived — the hint sentences too: “在上中宫里，3 只能填在 r3c5”
    • AddedRussian arrived — the hint sentences too: “В блоке сверху по центру цифра 3 может стоять только в r3c5”
    • AddedPolish arrived — the hint sentences too: “W bloku u góry pośrodku cyfra 3 może stać tylko w r3c5”
    • AddedTurkish arrived — the hint sentences too: “Üst orta blokta 3 yalnızca r3c5 hücresine girebilir”
    • AddedVietnamese arrived — the hint sentences too: “Ở khối trên giữa, số 3 chỉ có thể vào ô r3c5”
    • AddedThai arrived — the hint sentences too: “ในบล็อกบนกลาง เลข 3 ลงได้เฉพาะที่ช่อง r3c5”
    • FixedA row with no numbers in it no longer collapses. On a 500px board that row was only 17px tall
    • AddedThe rules page now explains with board diagrams — four topics, from the last free cell to notes, with the notes drawn inside the cell
    • AddedArabic arrived — the hint sentences too: “في المربع العلوي الأوسط، لا يمكن للرقم 3 أن يقع إلا في الخانة r3c5”
    • ChangedThe Arabic pages read right to left. The board and the number pad stay as they are — one puzzle number must not draw a different picture in each language
    • FixedTable headings now use the body font. The monospace face carries no Arabic, so its letters were pulled apart into fixed-width cells
    • AddedAll thirteen technique pages now carry a board diagram, with the notes drawn where the technique needs them
    • FixedThe Y-Wing hint now names the wing that matches the pivot's value. Half the time it said “if the pivot is 1” about the wing with no 1 in it
    • FixedThe small pencil marks in the explanation diagrams no longer get clipped on a phone, and the diagrams are bigger
14. 0.2.02026-09-05
    • AddedThe board now carries four readouts: score, difficulty, mistakes and time. The icon beside the clock pauses
    • AddedA digit that does not match the answer turns red on the spot and is counted, up to three. At three the board stops
    • AddedSettings arrived. Highlight the row, column and box; highlight the same digit; flag duplicates; count mistakes; quick entry; auto notes — six switches
    • AddedYour score climbs as you play: difficulty multiplier × (10 per correct cell − 20 per mistake − 30 per hint), plus a time bonus once you finish
    • ChangedEight buttons became four. Undo, erase, notes and hint stay on the row; quick entry and auto notes moved into settings
    • ChangedNew games are picked from a list that opens under the button. The warning that your progress will be lost can be turned off with “don't ask again”
    • ChangedFinishing a puzzle opens a panel with the difficulty, your time and your score
    • ChangedThe hint icon carries the number you have left
    • ChangedThe board and its digits are larger — up to 500px wide, with 42px digits on the number pad, so your eyes work less
    • ChangedThe selected cell is light blue and its row, column and box are a pale blue-grey. Where you are looking is now obvious at a glance
    • ChangedThe thick lines that split the 3×3 boxes and the thin ones between cells are different colours, so the nine blocks read first
    • ChangedThe accent colour moved from magenta to blue, and the header is now white
    • ChangedDigits are set in Roboto. Korean is drawn in the device's own font, so nothing heavy is downloaded
    • ChangedDifficulty is chosen from the row above the board. “New game” opens a list attached to the button
    • AddedA rules page arrived, covering the three rules and what row, column, box, clue and candidate mean
    • AddedAn awards page arrived. Twelve badges come from finishing each difficulty, from puzzle counts, from day streaks and from your times
    • AddedA daily-challenge calendar arrived. It shows which days you solved, month by month, and a past date opens that day's puzzle
    • ChangedDays you solved the daily puzzle are kept for 400 days. Only the last one used to survive, so the calendar lit a single square
    • ChangedThere is no leaderboard on awards or the daily challenge. Nothing is sent to a server, so there is nothing to compare against
    • AddedA tournament arrived. Three boards — medium, hard and expert — and everyone who comes that week plays the same three
    • AddedFinishing a tournament board records your time, and finishing all three shows the total. A replay only replaces the record if it was faster
    • ChangedThe header and the tab row beneath it became one row. Forty vertical pixels went away and the board rose by that much
    • ChangedOn narrow screens the menu folds into a hamburger. It closes on Esc or a tap outside, so it never sits over the board
    • ChangedThe board is 20px larger on phones. The side margins were narrowed to use more of the screen
    • ChangedUndo, erase, notes and hint have wider touch targets on phones. The icons are the same size; only the misses went away
    • Added“How to solve” gained a table that finds a technique from what you are seeing, so it is usable at the moment you are stuck
    • Added“Rules” now names the four things beginners actually trip on: guessing, skipping notes, reading only cells, and forgetting the box
    • AddedThe daily-challenge page now says that solving a past date neither fills the calendar nor extends a streak. That was written nowhere before
    • AddedThe tournament page now gives an order for the three boards and three ways to cut your time
    • AddedThe awards page explains how the time badges are earned: they look at your best time, so one good run lights them for good
    • FixedLeaving a finished board and coming back gives you a fresh puzzle at the same difficulty, not the completed one
    • FixedArriving on a link with a puzzle number and then picking a new game keeps the new one. A refresh used to snap back to the first puzzle
    • AddedA puzzle you have already solved is not handed to you again. This browser remembers the last 300
    • FixedA hint is counted only when you place it. Opening one and closing it with “leave it” costs nothing
    • ChangedHints come in three pages — where to look, why, then what to place — so the answer does not arrive first
    • FixedPlacing a digit or undoing closes an open hint. An explanation that no longer matched the board used to stay on screen
    • FixedThe hint card opens over the number pad. On small screens it sat below the fold, so pressing hint looked like it did nothing
    • ChangedOpening a hint dims the board and leaves only the cells it points at lit. Where to look now arrives through the eyes
    • ChangedThe difficulty row is labelled “Difficulty:” and the current one wears a blue pill. Colour alone was hard to spot
    • ChangedOn wide screens the header and footer line up with the board's width instead of spreading to the edges of the screen
    • ChangedType is bigger: hint titles 13→19px, hint text and the note under the board 13→15px, the clock 15→16px
    • Changed“How to solve” moved from the header to the footer. The header keeps only the ways back to the game
    • AddedThe tournament runs monthly. A hundred players including you, with the time left counting down by the second
    • AddedTournament points come from every board you finish that month, not only the three set boards
    • ChangedThe players on the leaderboard are invented by this browser. The top 1% is paced at about one puzzle an hour
    • ChangedThe “redo · check · restart · settings” row under the board is gone. Restart lives inside “new game”, settings under the gear beside the clock
    • ChangedAll hundred scores are visible on the leaderboard, and opening it scrolls to your place
    • ChangedBetween 20% and 40% of entrants do not show up in a given month — people who register and never come are left as they are
    • AddedWhere you placed in past tournaments is kept. The awards page groups them by year and month
    • ChangedThree mistakes ends the game and sends you to a new board; there is no second chance. A limit you can undo is not a limit
    • ChangedPlayers carry names. They are handles like Comet and Lumen, never people's names
    • AddedThe time left sits beside “Daily” and “Tournament” in the menu — midnight, and the last night of the month
    • ChangedThe tournament moved from weekly to monthly. Weekly meant that someone arriving on a Sunday saw a contest a few hours long
    • AddedHovering an icon button says what it does: undo, erase, notes, hint, pause and settings
    • FixedThe settings, erase and undo icons were redrawn. Settings looked like a sun, and the eraser's underline had come loose
15. 0.1.02026-09-05
    • AddedSudoku opened. Four difficulties, no login, nothing to install
    • AddedHints give the reasoning instead of the answer — “7 fits only here in row 3” — and light the cells the reasoning rests on
    • AddedPlacing a digit clears it from the notes in the same row, column and box. You no longer erase twenty cells by hand
    • AddedUndo and redo go all the way back, one note at a time
    • AddedClose the tab and the puzzle is still there. It is kept in the browser and never sent to a server
    • AddedOn wide screens the number pad and hints sit beside the board, so reading a hint costs no scrolling
    • AddedTurn on “quick entry” to pick a digit once and then tap cells. Filling many cells with one digit stops being a round trip
    • AddedPause and restart arrived. Pausing covers the board — stopping the clock while the answer stays visible is not a pause
    • AddedA record panel sits under the board: best time and count per difficulty, and how many days in a row you have played
    • AddedAn “expert” difficulty arrived. The median backtrack count rises from 109 at “very hard” to 824
    • FixedDifficulty labels were corrected. Some boards were graded up merely for having many empty cells
    • Changed“Fill notes” became “auto notes”. Left on, it recomputes the candidates after every move
    • FixedCandidates removed by a hint no longer come back with auto notes. Progress like “the 4 in this box is on this line only” used to vanish every move
    • AddedEvery puzzle carries a number. Pass on the number or the link and someone else plays the same board
    • AddedPrinting gives you the board and its number, so you can solve on paper and reopen it by number
    • AddedHint techniques went from five to nine, adding hidden pairs, naked triples, hidden triples and X-Wing
    • FixedThe next hint remembers the candidates already removed. The same elimination used to be offered again and again
    • Rule changeDifficulty is now the hardest technique the puzzle needs. The label says what it asks of you — “Medium · up to hidden singles”
    • Rule changeUp to “very hard”, following the hints reaches the end. “Expert” boards need more than the nine techniques
    • AddedA daily puzzle arrived. The date is the puzzle number, so everyone plays the same board that day
    • ChangedThe day streak counts the daily puzzle only. A number you build by tapping one easy board a day means nothing
    • AddedThe site opens without a connection. One visit and the browser keeps the game and the writing
    • AddedEvery technique has its own page, so arriving from a search like “sudoku X-Wing” gives you the worked sentences
    • AddedEach technique page links four boards where that technique is the decisive one, to play right after reading
    • AddedHint techniques went from nine to twelve, adding Y-Wing, simple colouring and Swordfish
    • ChangedSome “expert” boards can now be explained to the end. Every one of them used to fall outside our techniques
    • Changed“Hidden single” was split into scanning a box and scanning a line. The logic is the same; the work your eyes do is not
    • FixedDifficulty labels were corrected. Some boards said “up to pointing pairs” while actually needing naked triples