What makes Medium different from Easy?
A Medium sudoku starts with about 35 numbers already filled in. An Easy one starts with around 43. That difference of eight squares might sound tiny, but it changes how the puzzle feels.
In Easy puzzles, you can usually solve a square just by looking at one row, column or box. In Medium puzzles, you often have to look at TWO of those at the same time to be sure of an answer. Sometimes you have to scan a whole row, then check the boxes that overlap it, then check the columns again — and only then will the answer pop out.
Medium is the level where the famous "Notes" technique really starts to earn its keep. If you’re still solving Easy puzzles in your head, that’s great — but on Medium, even sudoku grandmasters write down their candidates. Don’t feel like you’re cheating. If you’d like a quick refresher on the basics first, the classic 9×9 sudoku page has a friendly walk-through.
Three strategies that work at Medium
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Scan one number at a time
Pick a number, like 5. Look at each row in turn. If a row is missing a 5, see which empty squares it could go in (remember to check the columns and boxes too). Only one option? That’s your answer. Then move on to the next row, then the next number. This is sometimes called "cross-hatching".
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Use the boxes as your friend
Each 3×3 box must use 1 to 9. If a box already has 1, 2, 3, 4 and 5, you only need to find homes for 6, 7, 8 and 9 — a much smaller puzzle inside the puzzle. Solving small puzzles inside the big one is the heart of sudoku.
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Cross-check rows and columns
Trying to place a 7 in a box? If you can already see a 7 in two of the box’s three rows, the 7 must go in the remaining row. Now look at the columns in that row — the 7 is the only square left.
When to use the Hint button
Hint is a friendly safety net, not a failure. Tap a square you’re unsure about, then tap Hint — the right number appears. The hints counter ticks up by one, but there’s no penalty.
A good rule of thumb: if you’ve been stuck for two minutes and nothing new is appearing, take one hint. Often the hint will unlock several more squares because it gives you the missing piece in a row or box.
The opposite tactic also works — try to finish a Medium puzzle with zero hints. It’s a fun mini-challenge. If you can do it once, try to do it again. Then try to beat your time.
Common Medium mistakes (and how to avoid them)
- ⏩ Going too fast. Medium puzzles punish a quick guess — a wrong number can ripple through the rest of the grid before you notice.
- 📝 Forgetting to update your notes. After you place a real number, scan the row, column and box and rub out that number from any other candidates.
- 🎯 Only looking at one technique. Medium puzzles often need you to switch between scanning numbers and scanning boxes. If one isn’t working, switch.
- ✅ Skipping the Check button. If something feels stuck, the most likely reason is a wrong number from earlier. Check it.
Ready for the next step?
When Medium puzzles start to take less than 10 minutes, give Hard sudoku a try. Hard puzzles ask you to look at the same square from two or three angles — that’s when sudoku really starts to feel like detective work.
Looking for something completely different? Try our Killer Sudoku game. Same 9×9 grid, but with little cages that have target sums — it’s sudoku with a tiny bit of adding mixed in.
Frequently asked questions
How long should a Medium sudoku take?
Most kids finish a Medium puzzle in 10–25 minutes once they’re comfortable with Easy. If yours is taking longer, that’s fine — it’s a puzzle, not a race.
Should I use Auto Notes on Medium?
Try without first. If you get stuck, Auto Notes shows the legal options for every square — it’s a really useful learning tool. After a while you’ll naturally start filling in your own notes.
What if I make a mistake?
The mistakes counter at the top ticks up and the wrong number appears in red. Tap the square, tap Erase, then try again. There’s no game-over screen and no penalty.
Is Medium good for a 7 year old?
It can be, especially if they’ve already enjoyed a few Easy puzzles. Try one together — if it feels frustrating, drop back to Easy for a while. There’s no rush.
Why does the timer not stop when I take a hint?
On purpose — we want hints to feel like a friendly tool, not a "cheat" you avoid. The only thing the timer measures is how long you spent on the puzzle.
Try a different size
New to sudoku? Start with a smaller grid — you’ll learn the rules in a few minutes.