Kuadra
One rule · endless boards
Every number
hides a rectangle.
Kuadra is a calm, beautiful Shikaku puzzle. Split the grid so that every rectangle holds exactly one number — and covers exactly that many cells. That is the entire game. No arithmetic, no luck, no reading required.
Free to play · 13,500 boards · A new daily challenge every midnight UTC
The rule
One number.
One rectangle.
Its area.
Divide the whole board into rectangles so that each one contains exactly one number, and that number equals how many cells it covers. Cover every cell, once. Nothing overlaps, nothing is left over.
01
Read
A 6 is a rectangle of six cells — 1×6, 2×3, 3×2 or 6×1.
02
Draw
Touch the number, drag to the far corner, lift. It snaps to the grid.
03
Cover
When the last empty cell disappears, the board is solved.
Watch it solve itself
6 × 6
Every board has exactly one solution.
Kuadra's generator proves uniqueness before a puzzle ever ships, so you never have to guess — only deduce.
Every day
One board.
The whole world.
A single daily challenge, identical for every player on the planet, resetting at midnight UTC. Post your time, watch the board fill up through the day, and keep the flame alive.
-
Streaks that mean something
Solve the daily to extend the flame. Miss a day and it starts over — that is the whole thrill.
-
Live stats before you start
How many have solved it, the average time, and how long is left on the clock.
-
Missed a day? Play it anyway
The archive keeps every past daily. They don't post to the board, so take your time.
The ladder
From a coffee break
to a whole evening.
Start on a 5×5 that resolves in a minute. Finish, some weeks later, on a 25×25 Grandmaster board with three hundred clues and nowhere to hide.
Play now
The first three rungs.
Right here.
Three real boards, pulled straight from the packs the app ships — same generator, same single solution. Drag from a number to the opposite corner and let go. Nothing to install.
Easy · 5×5
Drag from a number to the opposite corner. The rectangle has to hold exactly one number, and cover exactly that many cells.
Solved.
0:00
The next board is a step up. In the app, a fresh one lands every midnight UTC.
Time
0:00
Boards solved
0/3
These three are the whole tutorial.
Easy is a coffee break, Medium is the first board that makes you stop and look, Hard is where deduction starts to feel like work worth doing. The app goes four rungs further.
Stuck is allowed.
Hint places one correct rectangle and leaves the rest to you. Tap any rectangle you have drawn to take it back, or Undo to step backwards.
Nothing here is saved.
Your times live in this browser tab and vanish with it. Streaks, stats and the leaderboard only start counting in the app.
Themes
Six palettes.
Or just follow your phone.
Warm Paper for daylight, Dark Premium for the last puzzle of the night, High Contrast when the grid has to be unmissable. Leave it on System and the app changes with your device.
Tap a palette — this page will wear it too.
Compete
Race strangers.
Or your friends.
Daily, weekly and all-time boards. Follow the players you keep bumping into, and the Following tab becomes a much smaller, much more personal race.
-
Follow anyone
Long-press a name on the board to follow. Follow each other and you both get told when one overtakes the other.
-
Send a reaction
A rocket for a blistering time, a fire for a streak. Small, silly, and the reason people come back.
-
Challenge a friend
Finish a board and send the exact same one to someone with a link. They get your time to beat.
Today's daily
An example board
Progress
Everything you solve,
kept.
A twelve-week activity map, your best and average time at every difficulty, and thirty-six achievements to trip over — from your first solve to a thirty-day streak.
-
Watch yourself get faster
Best and average times per difficulty, so the improvement is a number rather than a feeling.
-
Weekly quests and keys
A quest each week — three Hard solves with no hints, say — pays out keys that unlock packs and past dailies.
-
Guest or signed in
Play immediately with no account. Sign in whenever you want the streak backed up and synced.
One payment
Kuadra Complete.
Kuadra is free, and stays free. If you would rather have the whole thing at once, Complete opens every pack and switches the ads off — a single purchase, not a subscription. There is nothing recurring and nothing to cancel.
Hints are the one thing it does not buy. They keep costing keys, which you keep earning by playing — because a puzzle you have already paid to skip is not much of a puzzle.
- All 135 packs, every difficulty — 13,500 boards
- No ads, permanently
- 25 keys to start you off
- Restores on any device you sign into the same store with
Questions
New to Shikaku?
What is Shikaku?
A Japanese logic puzzle played on a grid dotted with numbers. You divide the whole grid into rectangles so that each rectangle contains exactly one number, and that number equals how many cells it covers. No arithmetic, no guessing — every board is reachable by deduction alone.
Is Kuadra free?
Yes — free to download and free to play. It carries light advertising, which we keep deliberately unobtrusive because a puzzle you play to unwind should stay that way. If you would rather skip both the ads and the pack unlocks, Kuadra Complete is an optional one-time purchase; it is never required to keep playing.
Do I need an account?
No. Everything is playable as a guest. Sign in with Apple or Google and your streak, stats and solved boards follow you to your other devices — and you appear on the leaderboards.
How hard does it actually get?
Easy boards are 5×5 and resolve in about a minute. Grandmaster boards are 25×25 and routinely take three quarters of an hour. In between sit Medium, Hard, Expert and Master — plus a Shapes set played on boards that are not square.
Can I learn it inside the app?
Yes. A three-step tutorial teaches the rule on a real board, and solver tips surface on the home screen as you go — corners first, ones are free, primes are strips.
Today's board is waiting
Fill the grid.
Clear your head.
iPhone, iPad and Android · Free to play