Free online sudoku, daily and no signup required

A few specifics worth knowing before you sit down:

Difficulty tiers. Each day's puzzle comes in multiple difficulty levels, from a gentler opening grid that relies mostly on naked singles and basic scanning, up to harder configurations that require candidate elimination and chain logic. You pick the level that fits your mood and your schedule.

A built-in timer. The clock starts when the puzzle loads. This is not a pressure mechanic so much as a personal benchmark. If you solve Tuesday's medium in eight minutes and Wednesday's in six, you know something clicked. The timer stops the moment the grid is complete.

No account, no streak anxiety. You do not hand over an email address. There is no streak counter threatening to reset if you miss a Saturday. The puzzle is simply there, you play it, and that is the transaction in full.

The daily puzzle details, at a glance

Greatest Games puzzles are free, require no signup, and publish one fresh puzzle per day that resets at midnight ET. The sudoku takes most players somewhere between three and fifteen minutes depending on difficulty, which fits comfortably inside a lunch break or a morning coffee.

A few solving tips that actually help

You do not need to be a sudoku veteran to finish a daily puzzle, but a small handful of techniques will get you through most medium and hard grids without resorting to guessing.

Start with the boxes that are most constrained. If a 3x3 box already has six or seven digits filled in, the remaining cells have very few legal candidates. Work those first. You will often unlock cells in adjacent rows and columns as a side effect.

Write in pencil marks early, not late. Pencil marks (also called candidates) are the small digits you note in a cell to track what is still possible. Players often resist using them because it feels like admitting uncertainty. Lean into them instead. Filling candidates into a nearly-empty row is tedious. Filling them into the last four cells of a column when you already know most of the digits is fast and often immediately reveals a singleton.

Look for naked pairs. When two cells in the same row, column, or box each contain exactly the same two candidates and no others, those two digits are spoken for. You can safely remove them from every other cell in that shared unit. This sounds narrow, but it cascades.

Avoid guessing on medium difficulty. If you feel forced to guess, it usually means there is a logical deduction nearby that you have not spotted yet. Back up, scan the most-constrained units again, and look for a digit that can only go in one place within a row or column even if the cell itself has multiple candidates. That technique, called a hidden single, resolves more stalled grids than any other.

On harder puzzles, X-wings are worth learning. An X-wing occurs when a particular digit appears as a candidate in exactly two cells across each of two rows, and both pairs are in the same two columns (or vice versa). That digit can be eliminated from every other cell in those two columns. It sounds elaborate but takes about thirty seconds to check once you know what to look for.

What else is on Greatest Games

Sudoku is the anchor of the puzzle library, but the Greatest Games hub has a full lineup of daily originals if you want something different after your grid is done. Wordly is a six-letter word-guessing game. Jumble is a tile-swap anagram. Shrooms is a star-battle logic puzzle for players who like their spatial reasoning with a little extra bite. Every game on the site shares the same rules: free, no login, one new puzzle per day.

Play today's puzzle

The grid is waiting. No account, no timer pressure, no ads asking you to upgrade. Just today's free daily sudoku, ready to go.