According to Official Guinness Records,
The fastest time to solve a 6x6x6 Rubik’s Cube is 1 min 19.46 sec, achieved by Max Park (USA) at Qualifornia 2018 in California, USA, on 6 May 2018.This is the first time Max has held this record.
For a complete list of 2018 records, please visit 2018 Guinness Records in United States.