How to Solve Sudoku Faster
Practical speed techniques — efficient scanning, smart notation, and the habits that cut minutes off your solve time.
Speed in Sudoku is not about thinking faster; it is about looking in the right place and not re-deriving what you already know. Fast solvers waste no scans, carry minimal notes and follow a fixed routine so their attention never wanders.
These are the highest-leverage habits, roughly in the order they will save you the most time.
Scan by digit, not by cell
Beginners stare at one empty cell and ask "what goes here?". Fast solvers pick a digit and ask "where can this go?" across a box or band, placing hidden singles in a rhythm. Cross-hatching — sweeping the rows and columns that already contain a digit to see which box cell survives — is the fastest way to fill the opening of any grid.
- Pick the most-placed digits first; they constrain the grid hardest.
- Cross-hatch box by box rather than cell by cell.
- Finish a digit across the whole grid before moving to the next.
Use Snyder notation, not full marks
Marking every candidate in every cell is slow to write and slow to read. Snyder notation marks a candidate only where a digit has exactly two spots in a box — exactly the marks that reveal hidden pairs and pointing pairs. You write far less, your grid stays readable, and the high-value patterns jump out.
Build a fixed routine
Always scan in the same order — say, digits 1 to 9 across boxes, then rows, then columns. A consistent routine means you never wonder where you have already looked, and your eyes learn the patterns. Combined with re-scanning a digit’s units immediately after placing it, this removes almost all wasted time.
Try it yourself
Tap a cell, then a number, to practise.
Frequently asked questions
- What is the fastest way to start a puzzle?
- Cross-hatch for hidden singles digit by digit. It places the most numbers in the least time and needs no pencil marks at all.
- Do pencil marks slow me down?
- Full marks can. Snyder notation — marking a digit only where it has two candidate cells in a box — gives you the useful patterns with a fraction of the writing.
- How do top solvers go so fast?
- A fixed scanning routine, scanning by digit rather than by cell, minimal notation, and instant re-scanning after each placement. Speed is consistency, not rushing.
More guides
Practice online
Put it into practice on free puzzles with hints, notes and four difficulty levels.
Play Sudoku