Catalog study 01 · 512 puzzles
Clue count does not tell the whole difficulty story.
In our catalog, Medium and Hard both have a median of 25 givens. Their solving paths differ. The full distributions explain why a clue count alone cannot distinguish those labels.
The question and the measure
We compared clue counts across the four grades in our 512-puzzle catalog. Each puzzle's grade comes from the highest-ranked technique used by the solver.
| Grade | Puzzles | Minimum | Median | Maximum |
|---|---|---|---|---|
| easy | 128 | 24 | 33 | 42 |
| medium | 128 | 22 | 25 | 37 |
| hard | 128 | 22 | 25 | 32 |
| expert | 128 | 21 | 24 | 32 |
Where the clue counts overlap
Each bar counts puzzles with that many givens. Filter a grade to see its distribution; the complete table remains available below.
Read all counts as a table
| Clues | easy | medium | hard | expert |
|---|---|---|---|---|
| 21 | 0 | 0 | 0 | 1 |
| 22 | 0 | 3 | 2 | 6 |
| 23 | 0 | 18 | 19 | 20 |
| 24 | 2 | 29 | 34 | 40 |
| 25 | 2 | 28 | 28 | 26 |
| 26 | 4 | 16 | 19 | 12 |
| 27 | 6 | 8 | 10 | 9 |
| 28 | 2 | 8 | 7 | 5 |
| 29 | 7 | 7 | 2 | 5 |
| 30 | 5 | 7 | 4 | 2 |
| 31 | 16 | 2 | 2 | 1 |
| 32 | 19 | 1 | 1 | 1 |
| 33 | 11 | 0 | 0 | 0 |
| 34 | 13 | 0 | 0 | 0 |
| 35 | 15 | 0 | 0 | 0 |
| 36 | 7 | 0 | 0 | 0 |
| 37 | 5 | 1 | 0 | 0 |
| 38 | 5 | 0 | 0 | 0 |
| 39 | 3 | 0 | 0 | 0 |
| 40 | 3 | 0 | 0 | 0 |
| 41 | 2 | 0 | 0 | 0 |
| 42 | 1 | 0 | 0 | 0 |
More givens, a higher stored grade
The first Easy puzzle has 24 clues and is solved with naked singles. The first Medium puzzle has 29 clues and also uses hidden singles. Compare the two puzzles below.
Why the counts overlap
A given removes candidates from the cells in its row, column and box. Its position and value affect which deductions become available. Two puzzles with the same number of clues can therefore call for different techniques.
Inspect a position where singles stop →