How to play | Point Paper

Every puzzle can be solved by reasoning alone. Printed parts are set in ink with a serif face; everything you add appears in blue.

Hints, checks and reveals

Hint explains one step that follows from your current board and highlights the squares involved. It never changes the board by itself.

Reveal appears inside a hint and fills in what that hint proved. It is counted separately from hints.

Check outlines any of your entries that don’t match the solution, with a dashed line. A red corner is different: it means an entry breaks a rule on its own, whatever the solution is.

If your board already contains a wrong entry, a hint says so instead of building on it.

Clock, pause and saving

The clock starts with your first move and stops while the page is hidden or paused. Pausing hides the board. Every move is saved in this browser, so you can close the tab and continue later. Progress doesn’t sync between devices.

Keyboard: arrow keys move, Ctrl/⌘+Z undoes and Ctrl/⌘+Shift+Z redoes. Tab leaves the board.

Sudoku

Fill every empty square with a digit from 1 to 9.
Each row, each column and each of the nine 3×3 boxes contains every digit exactly once.
The printed digits are fixed. Every puzzle has one solution and never needs a guess.

Pick a square, then a digit on the keypad or keyboard. Switch to Notes (or hold Shift, or press N) to pencil in candidates. Placing a digit clears it from the notes that share its row, column and box.

Difficulty is the hardest technique our solver needed: singles for Gentle, up to X-wings and XY-wings for Fiendish. All sudokus

Nonogram

Each number is a run of filled squares in that row or column, in the order given.
Runs are separated by at least one empty square.
Fill the squares you can prove, and mark the ones you know are empty. The picture is named when you finish.

Choose Fill or Mark empty, then tap a square or drag along a row or column. A drag only changes squares in the same state as the one you started on, and one undo takes the whole drag back. No right-click needed.

Difficulty is how much reasoning a row or column needs, plus grid size: Easy lines settle one at a time, Hard ones need a short "what if" test or a large 15×15 grid. All nonograms

Star Battle

Place one star in every row, every column and every outlined region.
Stars never touch each other, not even diagonally.
Mark squares you know are empty; every puzzle has one solution.

Tap a square once for a mark, twice for a star, three times to clear it. Drag across squares to mark them all as empty in one move.

Difficulty is the reasoning needed: Easy uses single squares and regions that fit in one line, Medium rules out squares that would block a region, Hard needs groups of regions that share rows or columns. All star battles

Takuzu

Fill every square with a disc or a ring.
No more than two of the same side by side in a row or column.
Each row and column has as many discs as rings.
No two rows are the same, and no two columns are the same.

Tap a square to cycle disc, ring, empty, or use the Disc and Ring buttons. Printed symbols carry a small dot and can’t be changed.

Difficulty is the rule you need most: pairs and gaps for Easy, counting for Medium, comparing whole lines for Hard. All takuzus

Futoshiki

Fill the grid so every row and column contains each number once.
Where a sign sits between two squares, the numbers must respect it: the open side faces the larger number.
Every puzzle has one solution and never needs a guess.

Works like sudoku: pick a square, then a number. Signs between squares are printed; the open side always faces the larger number.

Difficulty is how far the signs must be followed: single signs for Easy, chains of signs and pairs for Hard. All futoshikis