East the Beasts
Starts with a real, checked easy puzzle already in the grid below, change it however you like, or clear it and enter your own numbers from scratch, one square at a time. As you go, this page shows every number that could still legally go in each empty square, tells you roughly how hard the puzzle is so far, and lists which real solving techniques would help right now, so you can build a puzzle at the difficulty you actually want. Print is only turned on once what you have typed is a real puzzle with exactly one solution, checked the same way every other puzzle on this site is checked, never just trusted.
Would rather play a sudoku on screen than build one? Play today's puzzle at Proven Sudoku, free, in your browser, no account.
Your puzzle
Possible ways to solve it right now
Each one links to Proven Sudoku's real explanation of that technique. This tool checks for the basics through Locked Candidates and Naked/Hidden Pairs and Triples. A puzzle needing something past that, an X-Wing or beyond, is reported as Hard or harder rather than guessed at.
Why build instead of generate
Some people want to place their own numbers on purpose, spelling something out in the givens, matching a real puzzle from a book they are stuck on, or just seeing whether their own attempt actually holds up as a fair puzzle. This page is for that, the free generator on the printable Sudoku page is for a fresh random puzzle instead.
Print stays off until what you typed has exactly one solution, the same uniqueness check this site's own generated puzzles use. A board that breaks a rule, cannot be finished at all, or could be finished more than one way is not a fair puzzle, and this page says so plainly instead of letting it print.
Questions
Yes. Every square starts editable, whether you keep the random easy puzzle this page starts with or clear it and enter your own numbers from the very first square.
This page checks it for you. Print only turns on once what you typed has exactly one solution, the same check this site's own generated puzzles use, so you never print a puzzle that cannot be solved, or one with more than one right answer.
The hardest technique actually needed to finish the puzzle. Easy needs only Full House, Naked Single, and Hidden Single. Medium adds Locked Candidates and Naked or Hidden Pairs and Triples.
This tool only checks for a specific set of real techniques, through Naked and Hidden Triple. A puzzle needing something past that, an X-Wing or beyond, gets an honest Hard or harder label instead of a guess at a technique this tool never actually checked for. Every technique it can name links to a full explanation at Proven Sudoku.