How to Solve Sudoku When Stuck: Expert Tips to Break Free

There’s nothing better than getting into the groove and successfully completing a Sudoku puzzle in record time. Alas, those experiences tend to be the exception, not the rule. If you play Sudoku for long enough, then you’ll eventually run into difficulties. You’ll get stuck, and you’ll have little idea of the next move you can make.

Happily, there are plenty of things you can do that’ll help you to break free and discover the solution you’ve been searching for. While you can’t expect to win every Sudoku puzzle you sit down to complete, using the techniques we’ve outlined below will ensure you give yourself the best possible chance of success.

And remember: the more regularly you play Sudoku, the better you’ll play. At 247Sudoku.com, you can play Sudoku whenever you feel like, completely free of charge. You can select from four difficulty levels — easy, medium, hard, and expert — that’ll ensure you always have a challenge that’s right for your level.

OK, with that out of the way, let’s take a look at some of the most effective ways to break loose when it feels like you’ve run out of ideas.

Identifying Key Patterns

The only thing you need to complete a game of Sudoku is logic. Alas, knowing that doesn’t always help, especially when you’re stuck. One way to get things moving is to identify patterns in your Sudoku grids.

By identifying key patterns, you’ll find it easier to uncover a troublesome number and complete the rest of the puzzle. Also, once you’ve got this technique in your toolbox, you’ll find it more straightforward to complete puzzles in the future, too.

It’s easier to recognize patterns in easy and medium-level Sudoku puzzles, so begin your learning journey with those. It’s difficult to see patterns at hard and expert levels, especially if you don’t know what you’re looking for!

If you’re looking to get started, then we’d recommend reading up on naked singles and naked pairs. They’re common techniques that every student of Sudoku should learn; we’ll run through some more information about them further down the page.

Using Process of Elimination

Looking for a quick and easy way to figure out where a number should go? Then consider using the process of elimination. With this, you’ll look at the numbers that have already been included in the square, row, and column. It’s a simple enough approach that anyone can use. While it won’t save you in every scenario, you’d be surprised at how frequently this handy little trick will save the day!

By utilizing the process of elimination, you will be, in effect, ruling out the possibility of other numbers until you’re left with one number — in other words, the right answer. To get started, simply scan your grids, identify possible candidates, and see if you narrow down your selection enough to be left with a single number.

Employing Pencil Marks

Pencil marks aren’t just a handy tool — depending on the difficulty level you’re playing on, they could well be a necessity. If you can complete a Sudoku puzzle on an expert level without using pencil marks, then, well, we doff our cap to you!

This approach simply involves writing the numbers that could go in a square in pencil — that is to say, using a format that can be erased. You’re not committing to the numbers you pencil in; you’re just giving yourself a bit of a helping hand. It’s much easier to make sense of the board when you can see all the possibilities. In some cases, using the pencil mark strategy will show that a cell could only be one possible number. Of course, in other cases, you could find that there are six possible candidates. But hey, it’s a start!

Note: you don’t need to play with a piece of paper to deploy the pencil technique. At 247sudoku.com, you’ll find a small pencil in the bottom right of the page when you’re playing a game. Simply click that, and pencil mode will be activated.

Focusing on Individual Sections

It’s generally best to complete a Sudoku puzzle with the whole grid in mind. However, if you’re stuck, then try spending some time completing an individual section. If you can do that, then you might just unlock the numbers of other grids.

As you’ll already be aware, there’s a connection between grids in Sudoku. If you put a number in one, then it’ll affect more than the grid in which it’s placed — the row and column will be impacted, too.

The bottom line is, if you’re stuck on one number, then try filling in a number in another part of the grid. You might be surprised at what it can open up!

Applying Advanced Techniques

Sudoku was invented back in 1979, and today millions of people play it every single day. Over the years, a whole host of techniques have been developed that can make it easier to complete puzzles.

Some of the most common techniques include:

• The X-Wing
• The Swordfish
• Forcing Chains
• Nishio
• Unique Rectangle Type 1
• The XY-Wing

It’s worth reading up on these advanced techniques. If you’ve got all of these in your toolkit, then it’s unlikely you’ll ever be stuck on a Sudoku puzzle for too long!

Double-Checking Your Work

In Sudoku, every number placement counts. If you’ve played an incorrect number, then eventually you’ll run into difficulty. If you’ve gotten stuck and you can’t figure out why, then look at going back over your existing answers. You might discover that you’ve made a mistake somewhere along the line — and once you’ve made a correction, then everything else might well fall into place.

Managing Puzzle Fatigue

Regularly completing a Sudoku puzzle is a great workout for your brain. However, as with going to the gym, it’s also possible that you’ll overwork your brain. At that point, it doesn’t matter how many expert techniques you have in your locker — you’ll probably find it difficult to complete the puzzle. After all, you’ll be too tired.

As with most things, prevention is the best way to manage puzzle fatigue. Let’s take a look at some effective ways to keep puzzle fatigue at bay.

Play Regularly

You can think of your brain as a muscle. By “training your brain,” you’ll be increasing its capacity to work hard. The more you play Sudoku, the easier it’ll be for you to concentrate on the task at hand, deploy critical thinking skills, and complete puzzles. If possible, look at playing at least once a day. 247Sudoku.com is available on desktop, tablet, and smartphone browsers, and games are completely free of charge.

Know When You’re Tired

It’s not just more difficult to complete Sudoku puzzles when you’re tired. It’s more difficult to do anything when you’re tired. If you’ve had a bad night’s sleep or a long day at work, then don’t put your brain under more duress by forcing it to complete a Sudoku puzzle. It needs to rest!

Taking a nap can also be an effective strategy when you’re stuck on a puzzle, too. You’ll likely feel more confident about completing the puzzle when you’re feeling refreshed. It’s the human version of “turning it off and then on again.”

Healthy Living

Healthy habits are good for just about every facet of your life. No one ever regrets investing in their wellness! By working out, eating healthy foods, and getting plenty of sleep, you’ll find it much easier to keep your mind in tip-top condition, which can help keep puzzle fatigue at bay.

Knowing When to Take a Break

It’s nice when you can complete a Sudoku puzzle as quickly as possible. Alas, that’s not always the case. There’ll be times when you’re sitting staring at a puzzle, wondering what the number you’re missing could possibly be.

It can be worthwhile powering through a little. Just because you don’t know the right number instantly, that doesn’t mean that you won’t get it with a little bit of work.

However, there might also come a point when it makes sense to take a break. You’re not giving up on the puzzle — you’re simply leaving it for the time being; you’ll come back ready to complete it!

Experienced Sudoku players know the power of temporarily leaving a puzzle to go for a walk. When they get back from their stroll, they can sometimes immediately see what the number is. They might have been staring at the puzzle for thirty minutes, yet when they get back from their walk, the answer is instantly obvious!

If you’re finding that you’re consistently struggling to complete Sudoku puzzles even though you used to find them straightforward, then it may be worthwhile taking an extended break. Leaving them for a week or two is completely fine — they’ll still be there when you return! In the meantime, you can try your hand at a different kind of puzzle, which will help to keep your mind sharp. For instance, you could try a crossword puzzle; you’ll find them at 247crossword.com.

DISCLAIMER: The games on this website are using PLAY (fake) money. No payouts will be awarded, there are no "winnings", as all games represented by 247 Games LLC are free to play. Play strictly for fun.