How Hardest Sudoku compares
A fair look at difficulty rating, ads, and assist behavior.
By The Hardest Sudoku Team · Last updated
TL;DR
How Hardest Sudoku compares to popular Sudoku apps and how the SE grade compares to other difficulty ratings — a fair, factual overview focused on objective difficulty, ads, and assist behavior.
Hardest Sudoku vs other Sudoku apps
Popular apps (sudoku.com, the NYT Sudoku, sudoku.coach and others) are excellent for a broad audience. Hardest Sudoku is narrower on purpose: objective difficulty and no assist that finishes a cell for you. The table compares feature presence, not quality.
| Feature | Hardest Sudoku | Typical Sudoku apps |
|---|---|---|
| Difficulty rating | Objective SE grade (Sudoku Explainer standard) | Usually named tiers (Easy/Medium/Hard/Expert) |
| Top difficulty | Up to monster grades (SE grade ~11+) | Typically caps around 'Expert' / 'Evil' |
| Ads during a solve | No mid-game or intrusive ads — nothing interrupts a solve | Varies; many free apps show ads mid-puzzle |
| Auto-fill / auto-hint | Never places a value for you; hints explain only | Often include auto-candidate or fill-a-cell hints |
| Focus | Hardcore classic-Sudoku training | Broad puzzle catalog, casual to expert |
SE grade vs other difficulty ratings
SE grade is the difficulty number from Sudoku Explainer: the higher the grade, the more advanced the logic a puzzle demands. Easy puzzles sit near 1.0–2.0; the hardest monsters reach roughly 11.0 and above.
| System | What it measures | Note |
|---|---|---|
| SE grade | Hardest required logic technique (reproducible solver) | Objective and comparable across any puzzle |
| Named tiers | Editorial / app-specific labels | Easy to read, but not comparable between apps |
| Clue count | Number of givens | Weakly correlated with real difficulty (17-clue puzzles can be easy or monstrous) |
Comparison reflects general, publicly observable behavior of these products and rating systems; specifics can change as apps update. Sources: product documentation; SudokuWiki.org; Sudoku Explainer rating method.