Can a Sudoku have more than one solution?

A proper one has exactly one. Every puzzle here is checked for a single solution before you see it.

Do you have to guess to solve Sudoku?

Not here. Every puzzle can be finished with named logic steps, the same ones the hints teach. If you're guessing, there's a move you haven't spotted yet. Take a hint.

Why is Sudoku so hard for me?

Usually it's one step you haven't learned yet, not the number of clues. The hint shows which one, and Practice a technique drops you right on it.

How do I get better at Sudoku?

Learn one new technique at a time. Start with hidden singles, then pointing. Play a level until it feels easy, then move up one.

Is Sudoku good for your brain?

It's honest mental exercise and it keeps you focused. Evidence that it prevents memory loss is thin, so I'd play it because it's fun.

SudokuSudoku

Daily Sudoku for October 21, 2026

Hints teach the move, not just the number.

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Errors: 0

Auto Candidate Mode

Keys: 1–9 enter a number, N toggles notes, arrows move, Backspace erases. On a selected empty square, rest on one digit spot and click or tap it to toggle that note. Auto candidates lists every empty square at once.

Why this Sudoku is different

I play Sudoku most days, usually the NYT on my phone, and I still get stuck. So I built the version I wanted. Every puzzle here is solved one step at a time, the way a person would, and the hardest step sets the level. Clue count has nothing to do with it. That's why Not Easy plays a lot like an NYT Medium, and why Expert is where X-wings and swordfish finally show up. New to this? Start with Easy. Want the same grid as everyone else today? Play the daily. When you get stuck, take a hint. It won't hand you a number, it shows you the move and tells you what it's called. Free, no download, and no account unless you want one.

Hints that name the move

The hint points at the cells, tells you what the step is called, and shows why it works. Want the long version? It links to the technique page.

Graded by the hardest step

The solver works every puzzle the way you would. Whatever its toughest step was sets the level, so Hard actually means hard.

Practice one technique

Pick a technique and the puzzle loads with the easier steps done, stopping right where you need it. Practice stays off your stats.

Stats on your device

Streaks, badges and a skill ladder live in your browser. Want them on another device? Sign in with an email link. No password.

Can a Sudoku have more than one solution?: A proper one has exactly one. Every puzzle here is checked for a single solution before you see it.
Do you have to guess to solve Sudoku?: Not here. Every puzzle can be finished with named logic steps, the same ones the hints teach. If you're guessing, there's a move you haven't spotted yet. Take a hint.
Why is Sudoku so hard for me?: Usually it's one step you haven't learned yet, not the number of clues. The hint shows which one, and Practice a technique drops you right on it.
How do I get better at Sudoku?: Learn one new technique at a time. Start with hidden singles, then pointing. Play a level until it feels easy, then move up one.
Is Sudoku good for your brain?: It's honest mental exercise and it keeps you focused. Evidence that it prevents memory loss is thin, so I'd play it because it's fun.