New to Sudoku and not sure where to start? This article will walk you through how to identify the easiest square to fill in Sudoku – helping you solve puzzles faster and smarter.
Why start with the easiest square?
When playing Sudoku, placing the first correct number can set the tone for the entire puzzle.
If you start in the wrong spot, it’s easy to get stuck or waste time backtracking.
That’s why learning to identify the easiest square to fill is a key strategy to boost your speed and accuracy.
5 ways to identify the easiest square in Sudoku
Here are some tips to help you quickly figure out which square to fill first – usually the simplest and most straightforward ones.
- Look for a row, column, or block missing only one number
This is one of the most common and easiest ways to start.
Scan for any row, column, or 3×3 block that already contains 8 out of 9 numbers. That means:
- Only 1 number is missing
- It’s easy to figure out what’s left
These squares are no-brainers – fill them in right away to open up the rest of the puzzle.
- Focus on squares surrounded by “helpful clues”
Look for empty squares that are surrounded by many filled-in squares.
The more information you have around a square, the easier it is to eliminate possibilities and find the correct number.
Pro tip:
Pay close attention to squares near the center of a 3×3 block, or where multiple rows and columns intersect.
- Use the “Naked Single” technique
A naked single is a square where only one number fits, based on Sudoku rules.
After eliminating numbers that already appear in the same row, column, and block, you might be left with just one possible option.
Example:
If a square can’t be 1, 2, 4, 5, 6, 8, or 9 (because those numbers already appear in the row, column, or block), the only possibilities left might be 3 or 7.
If only one of them fits – go ahead and place it!
- Scan the board by number
Pick a specific number (like 1) and check where it can or can’t go in each 3×3 block.
If in one block, there’s only one square where that number can go, then you’ve found a guaranteed move.
- Start with the most filled blocks
The more numbers a 3×3 block already has, the easier it is to figure out the rest.
Quickly scan all 9 blocks and pick one that already contains 5 or more numbers – it’ll give you more to work with.
Tips for Sudoku beginners
- Don’t try to solve the entire puzzle at once. Break it down into parts.
- Use a pencil (or the note feature if you’re playing online) to jot down possible numbers.
- You don’t have to fill squares in order. Start with the easiest ones to make progress faster.
Try Sudoku for free — new puzzle every day!
Put these tips into practice now:
Play Sudoku for free at Sudoku.com.vn
- New challenges every day – 3 difficulty levels: Easy, Medium, Hard
- Available on mobile, tablet, and desktop
You might also like:
- How to start solving a Sudoku puzzle
- Why is Sudoku so addictive?
- How to use the “Naked Single” technique effectively
