Sudoku Solver

About the Sudoku Solver

This free Sudoku solver takes any classic 9×9 puzzle and finishes it for you. You can use it to check your own answer, get past a spot where you are stuck, or watch how a board unravels one logical move at a time. The solving runs directly in your browser and there is nothing to install. The only time anything leaves your device is the optional photo scan, where the photo is sent to our server just to read the numbers and is never stored.

Unlike a puzzle you simply play, the solver is a tool: you type in the given numbers, and it does the deduction. That makes it handy when you have a Sudoku from a newspaper, a book, or another app and want the solution — or when you would rather learn the reasoning than just see the finished grid.

Scan a Sudoku with Your Camera

You do not have to type the puzzle at all. Press Scan a photo, point your camera at the Sudoku — a newspaper, a book, a printout, or another screen — and line the grid up inside the frame. The scanner finds the board, reads the printed digits, and fills the grid for you in about a second.

No scanner is perfect, so the tool is honest about uncertainty: any cell it is not sure of, and anything that breaks Sudoku rules, is highlighted for you to double-check. Fix those few cells if needed, then press Show solution or Hint as usual. For the best result, get close enough that the puzzle fills the frame, and keep your fingers off the grid itself.

• Works with printed puzzles, books, newspapers, and puzzles on screens.
• Uncertain cells are highlighted — you check a few cells, not the whole board.
• The photo is used only to read the numbers. It is processed in memory and never stored.

How to Solve a Sudoku Puzzle Here

Entering a puzzle takes a few seconds. Select any cell, then type a digit from 1 to 9 or tap it on the number pad. To remove a number, press 0, Backspace, or the Erase button. When your clues are in, pick one of two modes.

• Press Show solution to fill the whole board instantly with the correct answer.
• Press Hint to reveal only the next cell that follows from clear logic, highlighted and explained.
• If two of your clues clash, the conflicting cells turn red so you can fix them before solving.

Solve Instantly, or Step by Step

The instant solve is powered by a fast logical engine that also checks whether your puzzle is valid. If the board has no solution, or more than one, the solver tells you rather than guessing.

Hint mode is for learning. It walks you through the puzzle one move at a time using real solving techniques — naked and hidden singles to place a digit, then locked candidates (pointing and claiming), naked and hidden pairs and triples, and single-digit patterns like X-Wing, Swordfish, and XY-Wing to narrow the options — and explains the reasoning behind each move in plain language.

Solver, or Just Play?

The solver is best when you already have a puzzle and want the answer or the reasoning. If you would rather solve a fresh board yourself, or learn the techniques in depth, these pages are for you.