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	571
Std. Deviate	93
Minimum	60
Maximum	1706

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	1706	2011-01-22
2	60	2024-12-10	1215	2013-07-09
3	355	2017-06-09	1086	2006-10-14
4	357	2019-08-09	1067	2011-06-30
5	362	2015-06-29	1037	2010-04-21
6	369	2020-07-10	978	2022-01-28
7	370	2018-01-17	977	2008-10-29
8	370	2013-05-02	958	2009-11-18
9	370	2019-03-13	943	2010-02-06
10	371	2020-08-09	942	2013-03-06
11	373	2013-05-03	921	2012-02-04
12	376	2013-05-01	917	2010-12-25
13	377	2007-06-16	915	2013-08-21
14	379	2017-10-13	894	2007-09-07
15	381	2017-04-11	892	2009-08-08

Number of People Who Solve a Sudoku

Most Difficult Sudokus

These Sudokus have been solved lest often: