Easy Sudoku

What makes a Sudoku easy

Difficulty in Sudoku is mostly about how many cells you can solve without holding anything in your head. An easy board is generous with its givens, so at almost every point in the solve there is at least one cell where a digit is forced by a single row, column or box.

That means you can work the whole grid one cell at a time and never need to track candidates. You will rarely need more than the first technique — find the digit that has only one place left to go, write it, and the board opens up a little further.

It is the right level for learning the shape of a grid, for a five-minute break, and for warming up before something harder. It is also the level most people can finish reliably, which matters more than it sounds: an unfinished puzzle teaches you nothing.

How to solve an easy board

Scan by digit rather than by cell. Pick a number that already appears several times, then look at each 3×3 box that is missing it and see how many places are left. On an easy board you will regularly find a box where only one cell can take it.

When scanning stops producing, switch to rows and columns and look for the last free cell — a line with eight digits already in it hands you the ninth. Alternating between the two views is usually enough to finish an easy grid without ever writing a candidate.

If you find yourself wanting pencil marks, you are ready for the next level up.

Every board has exactly one solution

Boards here are carved a cell at a time, and any cell whose removal would leave the grid with two valid answers is put straight back. That is what makes the 45-ish clue count on this page a difficulty rather than a gamble: there is always a deduction available, so you never have to guess and back out.

If you cannot find the next move, the honest fix is a technique rather than a hint. The techniques index covers them in the order they start paying off — or paste the grid into the solver and ask for one digit rather than the whole answer.