How do you play Sudoku?

Fill the 9x9 grid so every row, column, and 3x3 box contains the digits 1-9 exactly once. Click a cell and type a digit or use the on-screen number pad.

What is the goal in Sudoku?

Complete the grid without repeating a number in any row, column, or box, then move on to the next puzzle. Every board is designed to be solved by logic alone.

What are the controls for Sudoku?

Click or tap a cell to select it, then type digits 1-9 on your keyboard or use the on-screen pad. Notes and helper tools are available inside the app.

Is Sudoku free to play?

Yes, this Remarkable Games version runs free in your browser with no registration required.

Can you play Sudoku on mobile?

Yes, the responsive layout and tap controls work on phones and tablets as well as desktops.

What are the best tips for Sudoku?

Start with singles, use notes to track candidates, and re-scan each 3x3 box whenever you feel stuck rather than guessing.

Does Sudoku include hints or notes?

Yes, the interface supports note-taking, duplicate highlighting, and mistake checking to help you solve logically.

Sudoku

Solve classic 9×9 Sudoku boards with an intuitive interface, note-taking support, and auto-check.

Gameplay overview

Logic number placement

Remarkable Games’ Sudoku offers a clean web implementation of the classic puzzle. Each grid is solvable with logic, letting you toggle notes, highlight duplicates, or check mistakes. Finish a board to unlock another and keep your streak going.

Your objective

What you are trying to achieve

The goal of Sudoku is simple to state and satisfying to complete: fill the 9x9 grid so every row, column, and 3x3 box contains the digits 1 through 9 exactly once. Every puzzle here is solvable by logic, so you never need to guess.

Finishing a board unlocks another and keeps your streak going. Notes, duplicate highlighting, and mistake checking are there to help you reason rather than rush.

Controls

Keyboard or mouse

Click / Tap a cell to select it.
Type digits 1–9 on your keyboard or use the on-screen number pad to fill cells.
Use note mode to jot candidates; toggle tools if provided (check instructions inside the app).

Beginner guide

Your first few minutes

Sudoku rewards method over speed, so begin with the cells that can only hold one number.

Scan each row, column, and 3x3 box for a digit that has only one possible home, and place those singles first.
Turn on note mode and pencil in candidates for cells you cannot solve yet, then remove them as you eliminate options.
Check each 3x3 box for missing digits and cross-reference the rows and columns that pass through it.
Use duplicate highlighting and the check-mistakes tool to catch errors early instead of building on top of them.
Avoid guessing; if a board feels stuck, re-scan the whole grid, because there is always a logical placement hiding somewhere.

Advanced tips

Think systematically

Start with singles—rows, columns, or boxes that only allow one number.
Use notes to track candidates and clear them as you eliminate options.
If stuck, scan each 3×3 box for missing digits and cross-check rows/columns.

Why play it?

Brain workout

Classic rules with a modern interface and responsive layout.
Great for daily logic practice during short breaks.
Source code available for developers interested in puzzle generation techniques.

Our take

Why this Sudoku implementation is worth bookmarking

Remarkable Games’ Sudoku doesn’t try to reinvent the rules; instead, it focuses on legibility and reliable input. Clear fonts, responsive cell selection, and optional helpers like notes and duplicate highlighting make it easy to stay in the logic flow instead of fighting the interface.

Because everything runs in the browser without registration, it is an excellent candidate for a “daily puzzle” tab—something you can revisit on any machine without losing time to setup. For developers and educators, the linked project offers a concrete example of puzzle generation and validation that can be studied or extended.

Who will enjoy it?

This version of Sudoku suits players who enjoy classic, pen-and-paper style grids but want digital conveniences like mistake checking and notes. If you are looking for themed story modes or heavy gamification it may feel minimal, but as a focused logic trainer it is very strong.

Frequently asked questions

Need a quick answer?

How do you play Sudoku?: Fill the 9x9 grid so every row, column, and 3x3 box contains the digits 1-9 exactly once. Click a cell and type a digit or use the on-screen number pad.
What is the goal in Sudoku?: Complete the grid without repeating a number in any row, column, or box, then move on to the next puzzle. Every board is designed to be solved by logic alone.
What are the controls for Sudoku?: Click or tap a cell to select it, then type digits 1-9 on your keyboard or use the on-screen pad. Notes and helper tools are available inside the app.
Is Sudoku free to play?: Yes, this Remarkable Games version runs free in your browser with no registration required.
Can you play Sudoku on mobile?: Yes, the responsive layout and tap controls work on phones and tablets as well as desktops.
What are the best tips for Sudoku?: Start with singles, use notes to track candidates, and re-scan each 3x3 box whenever you feel stuck rather than guessing.
Does Sudoku include hints or notes?: Yes, the interface supports note-taking, duplicate highlighting, and mistake checking to help you solve logically.