How to Solve Easy Sudoku Puzzles

Easy sudoku puzzles are designed to be solved with just three techniques. You don't need advanced strategies, pencil marks, or trial and error. If you learn these methods and apply them systematically, you will solve every easy puzzle — guaranteed.

What Makes a Puzzle "Easy"?

Easy puzzles have more clues than harder ones — typically 35 or more pre-filled cells out of 81. More clues mean more constraints, which means more cells with obvious answers. The logic chains are short: most deductions require checking just one or two groups before the answer becomes clear.

Easy puzzles are also designed so that every step can be solved with naked single logic — meaning at least one cell always has only one possible digit. You never need to consider two cells simultaneously or use elimination chains. One cell at a time, always.

Technique 1: Last Remaining Cell

This is the simplest pattern in all of sudoku. Look at any row, column, or box that has eight of its nine cells filled in. The ninth cell has only one possible digit — the one that's missing from the other eight.

How to apply it:

1. Scan each row for rows with only one empty cell.
2. The missing digit from 1–9 is the answer for that cell.
3. Repeat for columns and 3×3 boxes.

On easy puzzles, you'll often find several of these immediately. Fill them in first — each one you place makes other cells easier to solve.

Example: A row contains 1, 2, 4, 5, 6, 7, 8, 9. The only missing digit is 3. The empty cell in that row must be 3.

Technique 2: Naked Single (Process of Elimination)

When no row, column, or box has just one empty cell, move to this technique. For any empty cell, eliminate every digit that already appears in its row, column, or box. If only one digit remains, that's the answer.

How to apply it:

1. Pick any empty cell.
2. List the digits already present in its row. Cross those off 1–9.
3. List the digits already present in its column. Cross those off too.
4. List the digits already present in its 3×3 box. Cross those off.
5. If exactly one digit remains, write it in. That's your answer.
6. If more than one digit remains, move to a different cell and try again.

On easy puzzles, this process will always produce at least one answer somewhere on the grid. Keep cycling through empty cells until you find it.

Example: An empty cell sits in a row that already contains 1, 3, 5, 6, 8 — eliminating those five digits. Its column already contains 2 and 7 — eliminating two more. Its 3×3 box already contains 4. After all three checks: 1, 2, 3, 4, 5, 6, 7, 8 are ruled out. Only 9 remains — that cell must be 9.

Technique 3: Scanning for a Single Digit

When you're stuck on individual cells, zoom out and focus on one digit at a time. This is called scanning.

How to apply it:

1. Pick a digit — let's use 7.
2. Find all the 7s already placed on the grid.
3. For each 3×3 box that doesn't have a 7 yet, look at the empty cells inside it. Cross out any empty cell that shares a row or column with an existing 7.
4. If only one empty cell remains in that box, it must be 7.

Scanning works best for digits that appear frequently on the grid already — the more 7s (or whatever digit you choose) are placed, the more constraints exist, and the easier it is to pin down the remaining ones.

Tip: Start scanning with the digit that appears most often in the current puzzle. If there are already seven 4s on the board, scanning for the last two is very fast.

A Step-by-Step Solving Strategy

Combine all three techniques into a repeating loop:

1. Quick scan: Look for any row, column, or box with only one empty cell. Fill those in immediately.
2. Naked singles: For each empty cell, check its row, column, and box. If only one digit is possible, fill it in.
3. Digit scan: Pick the digit that appears most on the grid. Scan each incomplete box to see if only one cell can hold that digit.
4. Repeat. After each digit you place, go back to step 1. New placements unlock new deductions.

On easy puzzles, this loop will solve the entire grid without ever getting stuck.

Common Mistakes and How to Avoid Them

• Checking only two of the three groups. Always check the row, the column, AND the box. Missing one group is the most common source of errors for beginners.
• Placing a digit before fully eliminating. Don't stop eliminating after finding two remaining candidates — keep going. The third constraint (row, column, or box) might eliminate one more, leaving you with a definite answer.
• Guessing when stuck. If no technique is yielding results, don't guess — re-examine. On easy puzzles, there is always a logical next step. Try scanning a different digit, or revisit cells you skipped earlier.

Practice Makes the Loop Automatic

The first time you apply these techniques, solving a puzzle might take 20–30 minutes. That's completely normal. After a dozen puzzles, the loop becomes automatic — you'll start seeing naked singles and scanning opportunities without consciously looking for them.

Speed is a side effect of pattern recognition, and pattern recognition comes from repetition. Focus on accuracy first.

Ready to Practice?

Apply what you've learned on a real puzzle. Easy puzzles are ideal — every step uses the techniques described in this article.

Play a free Easy Sudoku puzzle →

Once easy puzzles feel comfortable, level up: The Elimination Method →