- Easy puzzles always have at least one cell where only one digit is possible
- Start by scanning for rows, columns, or boxes that are nearly complete
- A Naked Single is any cell with exactly one remaining candidate
- Work the most-constrained areas first — they have the fewest options to check
- Never guess; if you're stuck, slow down and check candidates more carefully
Step 1: Scan for Nearly-Full Units
Before writing anything, look at each row, column, and box. Find the ones that already have 7 or 8 digits filled in. These are your easiest wins — the missing digit is the only one that can go there. Fill those in first.
Step 2: Cross-Hatch for Each Digit
Pick a digit — say, 5. Look at each 3×3 box one at a time. For each box, identify which rows and columns already contain a 5. Any cell in the box that sits in one of those rows or columns cannot hold a 5. If only one cell in the box is left, place the 5 there.
Work through all nine digits this way. On an Easy puzzle, this cross-hatching phase alone often solves 20–30 cells.
Step 3: Apply Naked Singles
For cells that still have multiple candidates after scanning, check each one: cross off every digit that already appears in the same row, column, or box. If only one digit survives, that is the cell's answer.
This technique — called a Naked Single — is the workhorse of Easy and Medium Sudoku. Most cells on an Easy puzzle can be solved by scanning or Naked Singles alone.
Step 4: Use Hidden Singles When Stuck
If no cell has only one candidate, look at each unit (row, column, or box) and ask: for each digit 1–9, how many cells in this unit could hold it? If only one cell in the unit can hold a specific digit, place it there — even if that cell still has multiple candidates. This is a Hidden Single.
The Solving Loop
Easy Sudoku follows a simple repeating cycle:
- Find and fill any Naked Singles
- Find and fill any Hidden Singles
- Scan for new nearly-full units
- Repeat until the puzzle is complete
On a properly rated Easy puzzle, this loop will never dead-end. If you hit a moment where nothing is obvious, you have likely missed a Hidden Single somewhere — go back and check each unit carefully for digits with only one valid cell.
Common Beginner Mistake
The most common mistake is skipping pencil marks. On Easy puzzles, many players try to hold candidates in their heads. This works for the first few moves but causes errors as the grid fills in. Switch to notes mode as soon as the obvious moves run out.
Ready to practice? Open a free Easy puzzle and apply these steps live. Once you finish your first one cleanly, try a Medium puzzle to test whether the techniques stick.