Here is the full list of all 26 Beat Saber achievements. It takes around 25-30 hours to unlock all of the achievements on Windows.
Finish the tutorial.
Get total score 100 million or more.
Get total played time 24 hours or more.
Get 100 kilometers travelled hand distance or more.
Get rank S on at least 15 different levels on expert difficulty (solo free play only).
Get full combo on at least 15 different levels on expert difficulty (solo free play only).
Get rank S on at least 15 different levels on hard difficulty (solo free play only).
Get full combo on at least 15 different levels on hard difficulty (solo free play only).
Clear any level on expert difficulty without any modifiers.
Get full combo on any level on expert difficulty without any modifiers.
Get total 10 000 good cuts or more.
Get at least rank A on any level on normal difficulty without any modifiers.
Get at least rank S on any level on hard difficulty without any modifiers.
Get rank SS on any level on expert difficulty without any modifiers.
Clear any level on normal difficulty and get at least 50 combo without any modifiers.
Clear any level on hard difficulty and get at least 100 combo without any modifiers.
Clear any level on expert difficulty and get at least 500 combo without any modifiers.
Clear any level without any modifiers.
Clear any level with faster song speed modifier.
Clear any level with insta fail modifier.
Clear any level with disappearing arrows modifier.
Clear any level with battery energy modifier.
Clear 30 missions in campaign.
Clear final mission in campaign.
Clear all missions in campaign.
Clear 100 levels or more.