Sudoku and Suko are both grid-based logic puzzles you solve by pure deduction, so solvers naturally wonder how alike they really are. The short answer: Suko is close 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: 3×3
- Closeness to Sudoku: Close
What is Suko?
A 3×3 grid of 1–9 where four circled sums cover overlapping quads of cells and coloured groups carry their own totals. Here are the rules in full:
- Place the digits 1–9, each once, in the nine cells.
- Each of the four circles equals the sum of the four cells around it.
- The cells are also split into coloured groups, each with a given total.
See a Suko grid
Suko puts 1–9 in a 3×3 grid, with a circled number at each inner corner giving the sum of its four surrounding cells (colour groups add their own totals too). Here the top-left circle reads 12 — the sum of 1, 2, 4 and 5.
A corner circle (12) sums its four surrounding cells: 1 + 2 + 4 + 5.
Like its sibling Killer Sudoku in miniature, Suko is all about the combination reasoning of a cage — which digits add to this circle? Solve a few and Killer's cage sums feel easier.
What Suko shares with Sudoku
- The "distinct digits plus sum clues" idea is Killer Sudoku shrunk to nine cells.
- Solving means finding which digits fit each sum — Killer's combination logic exactly.
How Suko differs from Sudoku
- It is one 3×3 block, so there are no rows, columns or boxes — only the sums.
- All nine digits are used once across the grid, not once per line.
Do Sudoku skills transfer?
Like its sibling Sujiko, Suko drills the combination reasoning Killer Sudoku rewards — a quick way to sharpen "which digits add to this?" instincts.
Brush up on the technique that carries over: Killer Combinations.
The verdict
Suko is another pocket Killer: overlapping sums and colour totals on a single 3×3 block.
Prefer to stay with Sudoku?
If Suko appeals, these Sudoku variants scratch the same itch and you can read up on each here: