Statistics on Difficulty of Sudokus
There is now reliable, objective way to measure the difficulty of a given Sudoku. Therefore these statistics compiled from how fast or slow humans solved the Sudokus on the one hand, and how many people solved a given Sudoku on the other hand.
Average Solving Time
All times are given in Seconds.
Overall Statistics
| Average | 569 |
| Std. Deviate | 95 |
| Minimum | 60 |
| Maximum | 2617 |
Easiest and Hardest Sudokus
The Sudokus that were solved fastest/slowest on average.
| Easiest | Hardest | |||
|---|---|---|---|---|
| No | Mean Time [s] | Sudoku | Mean Time [s] | Sudoku |
| 1 | 60 | 2006-06-05 | 2618 | 2026-01-03 |
| 2 | 60 | 2026-02-07 | 1699 | 2011-01-22 |
| 3 | 351 | 2017-06-09 | 1205 | 2013-07-09 |
| 4 | 354 | 2019-08-09 | 1080 | 2006-10-14 |
| 5 | 362 | 2015-06-29 | 1063 | 2011-06-30 |
| 6 | 365 | 2018-01-17 | 1032 | 2010-04-21 |
| 7 | 366 | 2020-07-10 | 979 | 2008-10-29 |
| 8 | 368 | 2013-05-02 | 971 | 2022-01-28 |
| 9 | 371 | 2013-05-03 | 955 | 2009-11-18 |
| 10 | 374 | 2020-08-09 | 945 | 2010-02-06 |
| 11 | 374 | 2013-05-01 | 938 | 2013-03-06 |
| 12 | 375 | 2007-06-16 | 919 | 2012-02-04 |
| 13 | 377 | 2017-10-13 | 913 | 2013-08-21 |
| 14 | 378 | 2019-09-27 | 909 | 2010-12-25 |
| 15 | 379 | 2015-06-28 | 894 | 2009-08-08 |
Number of People Who Solve a Sudoku
Most Difficult Sudokus
These Sudokus have been solved lest often:
| Number | Sudoku |
|---|---|
| 1 | 2026-02-07 |
| 2 | 2006-06-05 |
| 38 | 2025-07-05 |
| 38 | 2025-08-02 |
| 39 | 2026-02-01 |
| 39 | 2025-12-07 |
| 41 | 2025-01-09 |
| 41 | 2025-07-06 |
| 41 | 2025-09-09 |
| 43 | 2025-09-18 |
| 44 | 2025-03-18 |
| 44 | 2025-07-09 |
| 44 | 2025-11-30 |
| 44 | 2024-08-29 |
| 44 | 2025-11-11 |