Scramble length

[yomaster]

I just need to know... what is the official scramble length? What I mean by "length" is that R U R' U R U2 R' would be 7. So how long do they make the scrambles in competition? I just want to know for the 2x2, 3x3, and 4x4. Thanks!

 

[MichaelP.]

25 moves is the usual, although in competitions they use an optimal scramble which can range anywhere from 16 (or 17?) to 20 moves. Please use the one answer question thread next time.

 

[danthecuber]

http://www.worldcubeassociation.org/regulations/#scrambling

 

[cmhardw]

Here are the official scramble lengths for all puzzles, including the required scrambling program for each. Also, yes the one answer question thread is a great place for questions like this in the future.

--edit--
Ninja'd by dan