--- title: "Find the Mistake Sudoku #23 | Sudoku Flow" description: "Sudoku puzzle #23: a half-finished board with 58 digits, 30 of them filled in by a player, and one of those is wrong. Find it in five seconds, then check the answer." url: https://sudokuflow.com/puzzles/find-the-mistake-23/ language: en --- [Puzzles](https://sudokuflow.com/puzzles/) / Find the mistake #23 [Find the mistake](https://sudokuflow.com/find-the-mistake/) # Find the mistake #23 One digit on this board breaks the rules. The game is half finished: some digits were printed with the puzzle, the others were filled in by a player. Give yourself five seconds before the video shows it. ## Reading the board ## Where to start This board has 58 digits and 30 of them are blue, so those 30 are the only suspects. The most crowded line is row 3, with 9 digits: a good place to start. [How to find a mistake in Sudoku →](https://sudokuflow.com/guides/find-a-mistake/) ## Try it here Tap the digit you think is wrong. Sudoku board for Find the mistake #23: ```text . 4* . | 7 9 6* | . 1 8 . . . | 2* 8* 1 | 4 . 6 6 1 8* | 5 4* 3* | 2 9* 7* ---------+----------+--------- 4 2* . | . 6 8 | 7 . . 3* . 1 | 7* 2 . | 6* 8 9 . 8* 6* | . 1* . | . 2* 4* ---------+----------+--------- 5* 3 4* | . 7 9* | . 6* 2* 1* 6 2* | . 3* 4 | . 7* 5 8 9* 7 | 6* 5* 2 | . 4 . ``` Digits marked * were filled in by a player; the others were printed with the puzzle.
Show the answer It's the blue 7 in row 5, column 4. Column 4 already has a printed 7 (row 1, column 4). A printed digit can't be wrong, so the blue one is. The right digit for that cell is 4.
Video transcript **On screen:** One number is wrong. / How fast did you find it? **Voice:** One number is wrong! Three! Two! One! Right there! How fast did you find it?
How fast did you find it? Tell us under the video. [Watch on YouTube](https://youtube.com/shorts/52IJBkOwqOI)
Embed this puzzle Copy this code to show the puzzle on your own site or blog. It links back here.
## More puzzles [![Find the mistake #22](https://sudokuflow.com/media/puzzles/find-the-mistake-22-en.jpg?v=ce2a3d139c)](https://sudokuflow.com/puzzles/find-the-mistake-22/): Find the mistake #22 11 s video [![Find the mistake #21](https://sudokuflow.com/media/puzzles/find-the-mistake-21-en.jpg?v=15f9ef203b)](https://sudokuflow.com/puzzles/find-the-mistake-21/): Find the mistake #21 11 s video [![Find the mistake #20](https://sudokuflow.com/media/puzzles/find-the-mistake-20-en.jpg?v=8bf1a3eb1d)](https://sudokuflow.com/puzzles/find-the-mistake-20/): Find the mistake #20 11 s video [![Find the mistake #19](https://sudokuflow.com/media/puzzles/find-the-mistake-19-en.jpg?v=84b0a41e57)](https://sudokuflow.com/puzzles/find-the-mistake-19/): Find the mistake #19 11 s video ![Sudoku app icon](https://sudokuflow.com/assets/app-icon.png) ## Want more boards like this? We also make a Sudoku app for iPhone, iPad, Mac and Android. There are no ads in it at all, it works offline, and when you ask for a hint it shows you the technique instead of just filling in a number. [App Store iPhone, iPad, Mac](https://apps.apple.com/app/apple-store/id6502922368?pt=125379530&ct=sudokuflow_web&mt=8) [Google Play Android](https://play.google.com/store/apps/details?id=com.rubigogames.sudoku&referrer=utm_source%3Dsudokuflow%26utm_medium%3Dweb%26utm_campaign%3Dsite) Sudoku Flow is made by Rubigo Games, the developer of the Sudoku app recommended on this site.