Crossword Difficulty Calculator

What Actually Makes a Crossword Hard

Crossword difficulty isn't just "big grid, hard puzzle" — a large grid with short, common words and few black squares can solve faster than a small, dense grid packed with long entries and sparse black-square breathing room. This calculator scores four contributing factors separately and combines them into a single difficulty figure, rather than relying on grid size alone.

The Formula

Size Factor = min(Grid Size ÷ 21, 1) × 25 Word Length Factor = min(Avg Word Length ÷ 8, 1) × 25 Word Density Factor = min(Word Count ÷ 78, 1) × 25 Black Square Factor = (1 − Black Square % ÷ 100) × 25 Difficulty Score = Size Factor + Word Length Factor + Word Density Factor + Black Square Factor

Each factor caps out at 25 points, so the maximum possible score is 100. Grid size is normalized against 21 (a large Sunday-style grid), word length against 8 letters, and word count against 78 entries — typical of a full-size themed crossword. Fewer black squares raises the score, since more white space usually means longer, more interconnected entries.

Worked Examples

Difficulty score for two sample grids
Grid	Size	Words	Avg length	Black %	Score	Label
Daily 15x15	15	78	5	16%	79.5/100	Hard
Sunday 21x21	21	140	6	12%	90.8/100	Expert

Difficulty Bands

Score-to-label mapping
Score range	Difficulty label
0 – 29.9	Easy
30 – 54.9	Medium
55 – 79.9	Hard
80 – 100	Expert

This is a heuristic scoring model built for relative comparison between grids, not an official crossword-industry difficulty standard.

Where This Calculation Matters

Puzzle constructors — checking whether a grid under construction lands in the intended difficulty tier before submitting it to a publisher.
Choosing a puzzle to solve — matching a grid's difficulty to the time available or the solver's skill level.
Tracking difficulty progression — publications that scale difficulty across a week (easy Monday to hard Saturday) can use this to check consistency.

How to Use This Calculator

Enter the Grid Size (for example, 15 for a 15x15 grid).
Enter the Word Count — the total number of entries in the grid.
Enter the Average Word Length of those entries.
Enter the Black Square Percent, the share of the grid taken up by black squares.
Select Calculate to see the difficulty score out of 100 and its label.

Related Calculations

For a similar difficulty-scoring approach applied to a different puzzle type, see the Riddle Difficulty Calculator or the Sudoku Solving Time Calculator.