🧩 Stuck on a sudoku puzzle? Pick your grid size below, type in the numbers you already have, and let the solver fill in the rest — instantly, right in your browser.
Type the numbers you already know into the grid and leave the rest blank. When you click Solve It, the tool checks every row, column, and box for conflicts, then works through the remaining empty cells until every square has a valid number. If your starting numbers break the rules of sudoku — the same digit twice in a row, column, or box — the tool will tell you exactly that instead of guessing.
If you'd rather work through the logic on paper before checking your answer here, browse our printable sudoku puzzles in four difficulty levels, or read our complete guide to solving sudoku for corner-starting strategy, pencil marks, and advanced techniques like X-Wing and Swordfish.