Sudoku and Fill-a-Pix are both grid-based logic puzzles you solve by pure deduction, so solvers naturally wonder how alike they really are. The short answer: Fill-a-Pix is distant to Sudoku. Below we lay out what the two share, where they part ways, and whether the skills you have built on Sudoku will carry over.
- Grid: Rectangular
- Closeness to Sudoku: Distant
- Also called: Mosaic, Fill-A-Pix
What is Fill-a-Pix?
Shade cells so each number equals how many of the cells in its 3×3 neighbourhood are shaded, revealing a picture. Here are the rules in full:
- A numbered cell tells how many of the nine cells in its 3×3 block - itself included - are shaded.
- Work out every cell's state until all clues are satisfied.
- The finished shading forms a picture.
See a Fill-a-Pix picture
Fill-a-Pix shades cells so each number equals how many of the cells in its 3×3 neighbourhood (itself included) are shaded, revealing a picture. Below, a solved snippet forming a small shaded block.
Shaded from 3×3 neighbourhood counts - the cells build a picture (here a plus).
Both are single-solution logic puzzles solved without guessing, and both lean on marking what a cell must or cannot be from the counts. But Fill-a-Pix is black-and-white painting from neighbourhood counts, not number placement - there is no row, column or region rule. A distant relative.
What Fill-a-Pix shares with Sudoku
- Both are single-solution logic puzzles solved without guessing.
- Both lean on marking what a cell must or cannot be from the counts.
How Fill-a-Pix differs from Sudoku
- It is black-and-white painting from neighbourhood counts, not number placement.
- There is no row, column or region rule - only the 3×3 clues.
Do Sudoku skills transfer?
No digit technique transfers, but a Minesweeper-style count instinct - "this clue is already satisfied, so the rest stay clear" - is the same forcing logic Sudoku sharpens.
The verdict
Fill-a-Pix shares Sudoku's count-driven deduction but paints a picture instead of filling digits.
Where to play it
If it was Sudoku you came for, the level is the choice that matters more than the variant - Fill-a-Pix and Sudoku part ways on the rules, but a Sudoku grid can be a two-minute warm-up or an hour of work depending on nothing but how much of it you are given.
Difficulty and type are two separate dials here: the type sets the extra rule, the level sets how much of the grid you start with. Easy Sudoku leaves 36 of the 81 cells filled, so there is always an obvious next move somewhere; Evil Sudoku leaves 23, with no easy moves at all. Take it at the gentler end while the pattern is still new, and move up once it stops being a fight.