What you just used
Every move in this puzzle was one of two ideas. A naked single looks at one empty cell and asks which digits can still go there; when only one is left, it goes in. A hidden single looks at one digit and asks where in a row, column or box it can still go; when only one cell is open to it, that is where it lives.
Easy puzzles on this site are built so those two moves are always enough. Medium and Hard boards add positions where neither works, which is where pencil marks and naked pairs come in.
What to play next
Fresh board, same two techniques, no prompts. Turn on Notes if you want to see the candidates.
Want the rules in writing and a 30 day practice plan? Read the beginner's guide. Or see all twelve techniques on the technique lessons page.
Frequently asked questions
Yes. It is a normal 9x9 puzzle with 43 given digits and one solution, generated and checked the same way as every board on this site. It was chosen because every step can be explained with the two beginner techniques.
No. The first three screens show the rules on this exact board: rows, columns and boxes each hold 1 to 9 once. Everything after that is practice.
Tap Hint. The first tap shows you where to look, the second outlines the cell, the third places the digit and explains why. Hints are free here; there is no score.
Ten to fifteen minutes for most first-time solvers. The first eight moves are guided, the remaining thirty are yours, and the puzzle remembers your progress if you close the tab.