Construct a grid under a symmetry of your choosing, check that it is a legal crossword layout, fill it, write the clues, and print it.
Click to block squares. With a symmetry chosen, the whole orbit of a square is blocked at once.
Validity
Counts
white0
blocked0
blocked %0
entries0
regions0
Symmetry
Click a square to select it; click again to switch between across and down. Type letters, use the arrow keys to move, Tab for the next entry. Or type the whole entry into the box on the right.
Current entry
—
Nothing selected.
Suggestions
Progress
letters0
entries done0
Across
Down
Saved as crossword.pdf, taking its name from the title above.
Page preview — US Letter, actual size.
What is checked
Connectedness. The white squares must form a single region (that is, given two white squares, you must be able to move from the first to the second using only white squares), which is a standard crossword convention. The check is a depth-first search; watch it run if you want to see the steps of the algorithm.
Every square checked. Each white square must belong to both an across entry and a down entry.
Entry length. Entries shorter than the minimum are flagged. The default minimum is three.
Symmetry. Choosing a symmetry makes a toggle act on the whole orbit of a square, so the grid stays symmetric by construction.