Sudoku for Beginners
Everything you need to solve your first Sudoku - from the basic rules to your first "aha" moment.
Sudoku looks intimidating at first. A grid full of numbers, a few cryptic rules, and no obvious place to start. But here's the thing: every Sudoku puzzle is built on one simple idea. Each row, column, and 3×3 box must contain the numbers 1–9, each exactly once. That's it. Once you understand that, the rest is just learning where to look.
The 3 Rules of Sudoku
Every Sudoku has exactly three rules:
- Each row contains 1–9, no repeats.
- Each column contains 1–9, no repeats.
- Each 3×3 box contains 1–9, no repeats.
There's no math involved - just logic. You never need to add, subtract, or calculate anything. If you can count to 9, you can play Sudoku.
4 Strategies That Will Get You Through Any Easy Puzzle
1. Scanning (Cross-Hatching)
Look at a 3×3 box and check which numbers are already placed in its row and column. By eliminating what can't go in a cell, you'll often find what must.
This is the single most useful habit for beginners. Start here every time.
→ Learn more about cross-hatching
2. Naked Singles
When a cell has only one possible number left - because every other number already appears in its row, column, or box - that's a naked single. Fill it in.
3. Hidden Singles
Sometimes a number can only go in one cell within a row, column, or box - even if that cell has other candidates too. That number is "hiding" among the possibilities.
4. Pencil Marking
Write small candidate numbers in empty cells. This helps you spot patterns and makes elimination much easier. Most apps (including ours) have a notes mode built in.
Tip: Start pencil-marking a single row or box instead of the whole grid. Less overwhelming, more progress.
5 Mistakes Every Beginner Makes (And How to Avoid Them)
- Guessing instead of deducing. If you're not sure, don't place a number. Use pencil marks instead.
- Ignoring the 3×3 boxes. Beginners often scan rows and columns but forget the boxes. Always check all three constraints.
- Trying to solve the whole grid at once. Focus on one area with the most given numbers. Small wins build momentum.
- Not using pencil marks. Your memory isn't as reliable as you think. Write candidates down.
- Giving up too early. Easy Sudoku puzzles are designed to be solvable with the 4 strategies above. If you're stuck, re-scan - you probably missed something.
What to Learn Next
Once you're comfortable with easy puzzles, here's your path forward:
- ✅ You are here: Beginner - Rules + Scanning + Singles
- → Easy Sudoku puzzles - perfect practice while you learn
- → Sudoku difficulty levels explained - how Easy → Master really works
- → How to Play Sudoku - step-by-step rules and first moves
- → Easy Strategies - Pointing Pairs, Box-Line Reduction
- → Sudoku Tips - 50+ tips for all levels
- → All Strategies - from Naked Pairs to X-Wing and beyond
Frequently Asked Questions
Is Sudoku a math puzzle?
No. Sudoku uses numbers, but there's no arithmetic involved. It's a pure logic puzzle. You could replace the numbers with letters or symbols and it would work the same way.
How long does it take to learn Sudoku?
Most people can solve an easy puzzle within 15–30 minutes of learning the rules. With a bit of practice, you'll get faster quickly.
What's the best difficulty to start with?
Start with Easy. These puzzles have more given numbers and can be solved with basic scanning and singles techniques. Move up when easy puzzles feel routine.
Do I need the app to learn Sudoku?
No - you can play on the website or print free PDF puzzles. The app adds a clean, distraction-free experience with built-in notes mode and daily puzzles.
What if I get stuck on a puzzle?
Re-scan the grid methodically: check each row, column, and box for naked or hidden singles. If you're still stuck, try pencil-marking an area you haven't explored. On easy puzzles, these techniques will always be enough.
Can I print beginner puzzles?
Yes. Our printable puzzles page has free weekly PDF packs in Easy through Master difficulty, in both A4 and US Letter format.
Ready to Start?
Pick an easy puzzle and try the scanning technique. You'll be surprised how quickly the numbers fall into place.