Printable Sudoku Generator with Four Levels and Solutions

How to use it

Choose the Level and the Number of puzzles, and set the Puzzles on each printed page.
Press Make puzzles. Write the Sheet number down, so that you can make the same sheet again.
Press Print puzzles and solutions: the puzzles print first, and the solutions start on a page of their own.
To check a puzzle from a book, paste its 81 cells into Solve a puzzle and press Solve and show the steps.

The four levels

Level 1, easy: every step is a naked single (a cell with only one digit possible) or a hidden single (a digit with only one place left in its row, column or box).
Level 2, medium: also locked candidates. If a digit in a box can only sit in one row or column (pointing), or in a row or column only in one box (claiming), it is removed from the rest of that line or box.
Level 3, hard: also naked pairs and triples (two or three cells that hold only the same two or three digits) and hidden pairs and triples (two or three digits that can only go in the same two or three cells).
Level 4, expert: the puzzle still has one solution, but the techniques of levels 1 to 3 cannot finish it. It needs an X-Wing (a digit that sits in two rows, in the same two columns) or trial and error.

How the puzzles are made

A full grid is made at random, then its givens are removed one at a time in a random order. At levels 1 to 3 a given is removed only when the solver can still finish the puzzle with the techniques of that level, and the result must need that level's hardest technique. At level 4 a given is removed only while the solution stays unique.

The number of givens does not set the level here. A puzzle with more givens can still need a hard technique, so compare the level and not the count.

What this page does not cover

Other sudoku variants, such as killer, samurai or puzzles with a diagonal rule.
Ratings from other solvers: the levels here follow the techniques this page uses, so another rating scale can give a different level.
Timers, saved puzzles or scores: the puzzles are made in your browser and printed, and nothing is stored.

Worked example: the first three steps

The example puzzle is 530070000 600195000 098000060 800060003 400803001 700020006 060000280 000419005 000080079. The solver fills three cells in its first three steps. R5C5 means row 5, column 5, and so on.

Each step is a naked single: the other digits already appear in that cell's row, column or box, so only one digit is left for it.

Step	Placement	Why
Naked single	R5C5 = 5	the only digit left for this cell
Naked single	R5C2 = 2	the only digit left for this cell
Naked single	R5C8 = 9	the only digit left for this cell

Frequently asked questions

Does every puzzle have exactly one solution?

Yes. Each puzzle is made so that only one grid fits its givens. Levels 1 to 3 are finished by logic alone, and level 4 is confirmed by counting the solutions by trial and error.

How is the level of a puzzle decided?

By the hardest technique its steps need. The solver takes the easiest step it can find each time, so a puzzle that singles can finish is level 1, and one that needs locked candidates is level 2.

Why does the solver say a pasted puzzle needs trial and error?

The techniques on this page cannot finish it. A person would then guess a digit and check whether the grid breaks. This page counts the solutions by trial and error instead, so the one answer is still found and shown.

Can I make the same puzzles again?

Yes. Write down the sheet number, then enter the same number with the same level and count. The page makes the same puzzles, in the same order, each time.

Are the puzzles I paste sent to a server?

No. The puzzle is read and solved in your browser. Nothing you paste is stored or sent to us.

Why are there not fewer givens for expert puzzles?

The number of givens does not set the level on this page; the techniques do. An expert puzzle can have as many givens as an easy one, so compare the level with the number of givens and not on its own.

Sources

Figures and text last checked on Tuesday, November 10, 2026.