Browse puzzles
Every puzzle carries a Peak Sudoku score from 1 to 100 – a consistent measure of how hard it is to solve. Pick a range and find precisely the right Sudoku puzzle.
The ten difficulty tiers
What each band actually demands, from a first-ever puzzle to the hardest the library holds.
BeginnerPeak Sudoku score 1–10
Perfect for a very first puzzle or a relaxing warmup, these grids can be solved through basic observation. There is no need for notation, as every step reveals an obvious missing number in a row, column, or block.
GentlePeak Sudoku score 11–20
This level introduces mild spatial deduction where numbers are restricted to specific lines, requiring the cross-referencing of intersecting rows and columns. It remains very approachable and can usually be solved entirely mentally without pencil marks.
EasyPeak Sudoku score 21–30
Here, pairs of numbers sharing two cells begin to appear, requiring their elimination from surrounding areas. It is a great starting point for players wanting to practice using basic corner notes (Snyder notation) to track candidates.
MediumPeak Sudoku score 31–40
Spotting triplets is required: three numbers hiding within three specific cells, demanding a bit more active memory. Full grid notation starts becoming highly beneficial here to untangle the overlapping possibilities.
TrickyPeak Sudoku score 41–50
This tier presents the challenge of finding groups of up to four numbers locked together in blocks or lines. It tests the ability to thoroughly scan the board and maintain clean, accurate pencil marks before tackling advanced logical patterns.
HardPeak Sudoku score 51–60
Welcome to the world of single-digit patterns like the famous X-Wing and Swordfish. The solver's perspective must shift away from individual blocks to analyze how a single number is distributed across entire rows and columns.
ToughPeak Sudoku score 61–70
This category introduces "bent" patterns like XY-Wings and meta-logic tricks like Unique Rectangles. Finding cells with exactly two options is essential, along with using logical chain reactions to eliminate candidates elsewhere on the board.
ExpertPeak Sudoku score 71–80
Chains of strong and weak links must be traced across the grid to prove that two different scenarios cannot both be false. This requires deep familiarity with advanced chain concepts, such as Skyscrapers, Two-String Kites, and simple Alternating Inference Chains.
ExtremePeak Sudoku score 81–90
These puzzles demand mastery of Almost Locked Sets and complex chains that span multiple digits and intersection types. It is a highly analytical experience requiring intense focus and a solid grasp of Sudoku graph theory.
DiabolicalPeak Sudoku score 91–100
Reserved for the most dedicated solvers, this tier relies heavily on branching logic and forcing chains where "what if" scenarios must be tested mentally. Puzzles at this level are incredibly taxing and often require advanced mental bifurcation to conquer.