How to Get Faster at Sudoku: A Realistic Guide

Most sudoku speed advice is bad. It tells you to scan faster, or to memorise patterns you haven't earned yet, or to use a stopwatch. What actually makes you fast is boring, and it's pattern recognition.

Watch a fast solver. They don't scan harder than you do. They scan less. Their eyes already know where to look, because they've seen the same shapes a hundred times. That's the whole game.

Here's what works, based on five habits that take a few weeks each to build but pay off forever.

1. Scan one digit at a time

New solvers scan a row, then the column, then the box. That feels thorough, but it's slow. Faster solvers scan one digit across the whole grid at once.

Pick a number. say, 5. Look at the top three rows and find every 5 that's already on the grid. Now ask: in the top-left 3×3 box, where can another 5 go? The 5 in row 1 and the 5 in row 2 rule out two of the three rows in that box. So a 5 in the top-left box has to be in row 3. If row 3 has only one empty cell in that box, you've just placed a 5.

Move to 6. Then 7. Then start over with 1. By the third digit, you'll notice you're moving faster, because each placement narrows the next scan.

2. Don't write pencil marks until you've earned them

This is the one that surprises people. Pencil marks are powerful, but on easy and most medium puzzles, they slow you down. You're spending twenty seconds marking up a cell that a basic scan would have solved in five.

The rule we use: don't pick up pencil marks until you can't find a single anywhere. If you've just scanned all nine digits and found nothing, then it's time. Otherwise, keep scanning.

When you do start, mark every empty cell. Half-marking is worse than not marking at all. it tricks you into thinking a cell has options that you haven't actually verified.

3. Use the box rule first

Beginners scan rows. Then they scan columns. Then they sometimes look at the box.

The box rule does more work than the row and column rules combined. Each box has nine cells, the same as a row or column, but it covers a smaller area. That makes hidden singles in boxes much more common than in rows or columns.

After every placement, ask: which boxes does this digit now constrain? Often the answer is two or three boxes, and you'll find another placement there. Pinging back and forth between boxes is how fast solvers cover most of the grid.

4. Build a "starter pair" you trust

Every fast solver has a routine for the first thirty seconds. Mine looks like this: scan for 1, scan for 5, scan for 9. The extreme digits. They tend to be the most constrained because the puzzle setter often clusters them.

Yours might be different. Some people swear by 3 and 7. The point is to have a consistent opening, so you're not deciding what to look at first every time. That decision burns seconds you'll never get back.

5. Stick with one difficulty for at least a week

People who hop between easy and expert and back never get good at either. The patterns at each level are different, and your eyes need repetition before they recognise them at a glance.

Pick a level you can solve in two or three sittings. Spend a week there. You'll feel boring solving the same difficulty over and over. Do it anyway. By the end you'll be twice as fast on those puzzles, and when you bump up to the next level, the basics will be automatic.

What about timers?

Use a timer if you want, but don't stare at it. Glance at it when you finish, not while you're playing. Watching the clock makes you rush, and rushing makes you miss the easy moves. You'll end up slower.

A better measure is how often you have to undo. If you're undoing more than once per puzzle, you're playing too fast. Slow down half a step and the speed will come back, more steadily.

Realistic times to aim for

After a month of practice, these are reasonable targets for the median adult solver:

• Easy: under 5 minutes
• Medium: under 12 minutes
• Hard: under 25 minutes
• Expert: under 45 minutes
• Evil: under 90 minutes

World-record holders are faster than this by an order of magnitude, but they also spend hours every day solving. For someone who plays one or two puzzles a day, those numbers are good.

The last thing

Speed isn't the point of sudoku. It's a side effect of getting good, and it's a nice signal that you've learned something. But if you're playing to relax. and a lot of people do. none of this matters. A slow, careful solve is the whole pleasure.

That said, if you want to get faster, start with the box rule and the one-digit scan. Those two habits alone will cut a minute or two off most of your solves within a week. Try it tomorrow.

When you're ready, play a few rounds at medium difficulty with these habits in mind. Or if you're already comfortable there, jump to hard and start practising pointing pairs.