How to Find Your First Sudoku Move Without Guessing
Practice a simple row, column, and box check with three original examples, including when there is not enough information to place a digit.
A Sudoku board can feel busy before you have placed a single digit. Instead of trying to understand the entire puzzle at once, choose one empty cell and ask a smaller question: which digits are already ruled out?
This guide gives you a starting routine and three short checks to try. It is not a complete solving method, a timed challenge, or a promise that every board has an immediately obvious move. The useful habit is learning to explain a placement before making it.
Start With The Three Checks
In classic Sudoku, each row, column, and 3-by-3 box must contain the digits 1 through 9 without repetition. A digit placed in a cell must satisfy all three groups, not just the row. Nikoli’s Sudoku rules describe the standard puzzle.
For one empty cell, a candidate is a digit that has not been ruled out by the digits already present in its row, column, or box. A candidate is a possibility, not automatically the answer.
Try this sequence:
- Look across the cell’s row. Which digits from 1 through 9 are missing?
- Look down its column. Remove any of those missing digits that already appear there.
- Check its 3-by-3 box. Remove any remaining digit that is already in that box.
- If exactly one candidate remains, you have a reason for that placement. If more than one remains, keep looking rather than choosing by preference.
Start with a row, column, or box that has several filled cells if that makes scanning easier. You are looking for a clear deduction, not proving how quickly you can inspect the whole board. Check the original clues carefully; deductions based on an earlier mistaken entry can carry that mistake forward.
Try Three Small Checks
These are original NewGames.ai teaching examples, not boards or answers from DaySudoku or another game. Each table lists the visible digits around one empty cell. It is not a complete puzzle. Digits are listed in numerical order, not in their positions on a board.
Work out which candidates remain before revealing the explanation. A digit may appear in more than one table row because the groups overlap, or because separate cells in different groups contain the same digit. What matters here is whether that digit is already excluded from the empty cell.
Check 1: One digit left
Which digit can go in this empty cell?
| Where | Digits already present |
|---|---|
| Its row | 1, 2, 3, 4, 6, 7, 8, 9 |
| Its column | 2, 8 |
| Its 3-by-3 box | 1, 2, 4, 6, 8 |
Reveal answer and reasoning
5 is the only candidate. The row already contains every digit except 5. Neither the column nor the box contains 5, so the other two checks agree.
Check 2: Use the column too
The row leaves two possibilities. Can the other clues settle the choice?
| Where | Digits already present |
|---|---|
| Its row | 1, 4, 5, 6, 7, 8, 9 |
| Its column | 2, 5 |
| Its 3-by-3 box | 4, 5, 7, 8 |
Reveal answer and reasoning
3 is the only candidate. The row is missing 2 and 3. The column already contains 2, so 2 cannot go here. Nothing in the row, column, or box rules out 3.
Check 3: Know when to wait
Can you justify a single digit using only these visible digits?
| Where | Digits already present |
|---|---|
| Its row | 1, 4, 5, 6, 7, 8, 9 |
| Its column | 5 |
| Its 3-by-3 box | 4, 5, 7, 8 |
Reveal answer and reasoning
Not yet: both 2 and 3 remain candidates. Neither the column nor the box removes either of the two digits missing from the row. These clues alone do not justify choosing one. On a full board, look elsewhere for another certain move and return later.
When Two Possibilities Remain
The third check is not a failed attempt. Recognizing that the supplied information is insufficient is part of careful play. On a full board, another area may provide a placement that changes the possibilities here later.
Do not turn a tentative candidate into a filled answer simply to make the board look less empty. If you keep notes, distinguish them from confirmed entries and update them after a justified placement. Check the game’s instructions before relying on any notes control; this guide does not assume a particular game provides one.
If your check leaves no candidates, pause. Recheck which row, column, and box you used, and whether you misread a digit. If you have already entered numbers, review those entries too. An empty candidate set signals a conflict in the current information, not a reason to insert a digit anyway.
A Routine For Your Next Puzzle
Before making the first move, try saying: “This digit is the only one left because these other digits are already present.” If you cannot explain the elimination yet, choose another cell to inspect.
After a certain placement, look again at the affected row, column, and box. One small change may make a nearby cell easier to reason about. That is a more manageable loop than repeatedly scanning every empty square without a plan.
When you return to these exercises, explain why each rejected digit cannot fit instead of only remembering the answer. You can close the explanations and try again. These are fixed examples, not fresh daily puzzles, and the page does not record attempts or scores.
From Practice To A Game
Our DaySudoku introduction is a starting point for exploring that game; use its official instructions for the current experience. The exercises above do not test or demonstrate its controls.
For a different style of reasoning, compare number, block, and color puzzles, or browse puzzle games. If you expect to leave a game unfinished, use the save checklist before assuming the board will be there later.
Keep useful guides nearby for another visit. A good first move is one you understand, even when it takes a little longer to find.
