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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

Average583
Std. Deviate97
Minimum361
Maximum1831

Easiest and Hardest Sudokus

The Sudokus that were solved fastest/slowest on average.

EasiestHardest
NoMean Time [s]Sudoku Mean Time [s]Sudoku
1 362 2019-08-09 1831 2011-01-22
2 364 2017-06-09 1251 2013-07-09
3 371 2015-06-29 1132 2006-10-14
4 373 2020-08-09 1100 2011-06-30
5 379 2017-04-09 1061 2010-04-21
6 380 2007-06-16 1028 2008-10-29
7 380 2013-05-01 1004 2009-11-18
8 382 2019-03-13 983 2010-12-25
9 384 2015-06-28 982 2018-07-13
10 386 2013-05-02 968 2013-03-06
11 387 2020-07-10 957 2012-02-04
12 388 2017-04-11 952 2010-02-06
13 388 2010-08-04 919 2013-08-21
14 388 2018-01-17 910 2012-02-14
15 391 2015-03-07 907 2007-09-07

Number of People Who Solve a Sudoku

Most Difficult Sudokus

These Sudokus have been solved lest often:

NumberSudoku
462020-09-20
522020-10-19
522020-10-21
542019-01-08
562018-11-08
562020-04-30
562020-06-26
572020-07-23
572020-07-24
572020-10-14
572020-08-22
592019-11-22
592020-03-14
592020-01-17
592020-09-13