What changes at Medium?
A Medium puzzle starts with 30 givens - six fewer than Easy. That doesn't sound like much, but it's enough that the board stops handing you free moves. You'll clear the obvious cells quickly, then hit your first honest pause: a grid where nothing jumps out and you actually have to look.
This is where Sudoku gets interesting. The puzzle is still gentle - every step is findable - but you start working for the solution instead of just reading it off. It's the level most people settle into for their daily grid.
Techniques that carry you through
Scanning for singles still does most of the job, but Medium is where a second idea earns its place:
- Hidden Single in Sudoku - A digit that can legally go in only one cell of a unit, even if that cell shows other candidates.
- Naked Pair - Two cells in a unit holding the same two candidates claim those digits, removing them elsewhere in the unit.
The naked pair is the big one to add here: two cells in a unit that share the same two candidates lock those digits away from everything else nearby, which often frees up a single you couldn't see before. It's the first taste of eliminating rather than just placing.
Is Medium the right level for me?
Medium is the default level on SudokuStreak, and for most players it is the right one. A useful test: if you finish an Easy grid without ever pausing to think, you are ready to move up. If you finish one but had to hunt for the last few cells, stay on Easy a little longer - the habits you build there are the same ones Medium rewards, just under less pressure.
The other signal is how a stall feels. On Medium you should get stuck a few times per grid, and each time the way out should be findable within a minute or two of proper looking. If you are stuck for much longer than that, it is usually not the difficulty - it is that your pencil marks are incomplete.
There is no prize for playing above your level. A grid that resists just enough to be interesting beats one that grinds you down, and the daily habit matters far more than the difficulty badge.
Where pencil marks start to matter
On Easy you can keep everything in your head. On Medium you'll hit a spot where you can't - and that's your cue to start pencilling in candidates. You don't have to mark the whole board; just note the possibilities in the region you're stuck on, and the naked pair (or a hidden single you'd missed) usually appears.
- Mark the tricky corner, not the easy one. Spend your notes where the grid is fighting back.
- Re-scan after every placement. One new number can turn three uncertain cells into certainties.
Ready for a real fight? Hard Sudoku is next - the level where scanning alone runs out and method takes over.
Prefer it on paper?
Every level here is also available as a printable sheet. The printable medium Sudoku page builds PDF pages at this exact difficulty - handy for a commute, a classroom, or anywhere a screen is in the way.
All five difficulty levels
Difficulty on SudokuStreak starts with how many digits the puzzle gives you, but the clue count is not the whole answer - and we can show that rather than assert it. On 31 August 2026 we generated 40 boards at every level and had our own solver finish each one, recording the hardest technique it was forced to use. The result was uncomfortable: 28 of the 40 Expert boards needed nothing harder than a hidden single, which is what Medium asks for. A 25-clue grid can still be a scan.
So Expert and Evil are no longer dealt straight from the generator. Boards for those two levels are measured first, away from the site, and only the ones that genuinely need the harder techniques are kept and handed out. That is what the last column below means: always is a floor the puzzle cannot fall below, usually is what the measurement found without one. The counts are for a standard 9×9 board:
| Level | Givens | Hardest technique needed (measured) |
|---|---|---|
| Easy Sudoku | 36 | usually naked single |
| Medium - you are here | 30 | usually hidden single |
| Hard Sudoku | 26 | usually hidden single |
| Expert Sudoku | 25 | always pointing or harder |
| Evil Sudoku | 23 | always box/line or harder |
The names are not standardised, though: "Expert" is the fourth rung of five here and the fourth of six elsewhere, and the hardest tier is called Evil on some sites and Extreme on others. Sudoku difficulty levels explained compares the common ladders and says what each level here actually asks of you.
Frequently asked questions
How many numbers does a Medium Sudoku puzzle start with?
Every SudokuStreak Medium puzzle on a standard 9×9 board is generated with 30 given digits, out of the 81 cells in the grid. Variants built on a different board set their own count for the same level - Samurai, for instance, is five overlapping 9×9 grids and fills each of them separately.
Do the puzzles always have exactly one solution?
Yes. However few givens a puzzle starts with, it has exactly one solution, and that solution is reachable by logic alone.
Do I ever have to guess?
No. Every puzzle can be finished by pure deduction. If you feel you have to guess, there is a technique on the board you have not spotted yet.
Is Medium Sudoku free to play?
Yes - every puzzle on SudokuStreak is free to play in your browser, with no account required. Signing in only adds streaks, scores and the leaderboard.
What is the difference between Easy and Medium Sudoku?
Six givens - 36 against 30. That sounds small, but it is the point where the board stops handing you free moves: you will clear the obvious cells quickly and then hit a grid where nothing jumps out and you have to look properly.
Can I print Medium Sudoku puzzles?
Yes. The printable medium Sudoku page generates PDF sheets at this exact difficulty, ready to print. You can start from the printable medium page.