Here is the full list of all 26 SUPERHOT achievements. It takes around 20-25 hours to unlock all of the achievements on Windows.
Find all secrets.
Kill over 1987 Red Dudes in endless mode.
Unlock all endless levels.
Beat all Challenges.
Become part of the community.
Launch every app in the system.
Get RED ending in every level of SPEEDRUNrt challenge.
Get RED ending in every level of SPEEDRUN challenge.
Kill 3 Red Dudes with one shotgun shot.
Upload a replay on killstagram.com
Kill an enemy by jumping on him.
Cut bullet with a katana.
Kill 100 Red Dudes with a katana.
Kill 100 Red Dudes using melee.
Complete the game.
Kill 100 Red Dudes with a shotgun.
Kill 100 Red Dudes with a rifle.
Get back to the system after being expelled.
Score 100 headshots.
Kill 2 Red Dudes with one katana throw.
Kill 100 Red Dudes with a pistol.
Complete SERV level.
Kill 3 Red Dudes with one rifle burst.
Complete SUBWAY level.
Shoot down a bullet with a bullet.