This tool lets you design the black-and-white layout of a crossword by clicking squares to toggle them between open (white) and blocked (black). It computes the across and down clue numbers automatically as you edit, and can enforce the rotational symmetry that published puzzles use — so you get a properly numbered blank grid ready to fill, print or save as a PDF.
How it works
Click any square to block or unblock it. With 180-degree rotational symmetry on, blocking one square also blocks the square diametrically opposite, matching standard crossword convention. The tool then numbers the grid using the standard rule: scanning left to right, top to bottom, a white square gets the next number if it starts an across word (its left edge is blocked or at the grid edge and the square to its right is open) or starts a down word (its top edge is blocked or at the grid edge and the square below is open). Grids range from 5×5 up to 21×21.
Clue numbering: how it matches published crosswords
The automatic numbering follows the same algorithm used by every major newspaper crossword. Scanning left to right then top to bottom, a square receives the next consecutive number if it starts at least one word. A square that starts both an across and a down entry gets just one number — the same number labels both the across and down clues. That is why clue lists say “7 Across” and “7 Down” can share a single number on the grid.
For illustration, consider the top-left corner of a 15×15 grid where the first square is open, the second is blocked, and the square below the first is also open. That top-left square starts a down entry (an open square below and a blocked top edge at the grid boundary) but not an across entry (the next square to the right is blocked, so no word runs rightward). It receives number 1 and is listed only as a down clue.
Grid size conventions
| Grid size | Common use |
|---|---|
| 15×15 | Standard American daily crossword |
| 21×21 | Standard American Sunday crossword |
| 13×13 | Compact British-style daily |
| 5×5 to 9×9 | Mini crosswords and kids’ puzzles |
The 15×15 grid is the default for most puzzle constructors. The 21×21 size allows for more theme entries and is used in larger Sunday editions.
Using 180-degree rotational symmetry
Published crosswords almost always have rotational symmetry: if you rotate the filled grid 180 degrees, the pattern of black and white squares looks the same. This is an aesthetic convention, not a rule, but solvers find it visually satisfying and constructors use it as a design constraint. Enabling symmetry here means you can design one quadrant of the grid and the mirror quadrant fills in automatically.
When symmetry is on, every click blocks the opposite corner simultaneously. This means you can never accidentally create an asymmetric layout. Turn it off only if you are making a novelty or theme grid where the shape itself is part of the puzzle’s visual design.
Printing and saving
Once you have your blocked pattern, use the browser’s print function or Save as PDF. The grid prints with its numbering exactly as shown. Nothing in your session is uploaded or stored — close the tab and the design is gone, so download or print before you do.