Here is the full list of all 45 The Forest achievements. It takes around 50-60 hours to unlock all of the achievements on Windows.
Play through entire game without killing or eating animals. Alone in Single Player or together in Multiplayer.
Finish Game
Craft all items
Kill all animal types and display heads
Grow all plant types
Craft 10 medicine items
Explore all caves
Revive 10 co-op players
Build a super long wall
Pass 50,000 steps
Eat all mushroom types
Cut down 1000 trees
Find all missing passengers
Catch fish with a trap. Alone in Single Player or together in Multiplayer.
Revive one co-op player
Kill 6 or more fish with a stick of dynamite. Alone in Single Player or together in Multiplayer.
Chop up 50 bodies
Collect all robot pieces
Eat an entire family
Set off 20 bombs
Collect all cassette tapes!
Kill shark. Alone in Single Player or together in Multiplayer.
Sleep on yacht
Killed downed enemy with rock
In Single Player, kill 100 cannibals
Kill a bunny. Alone in Single Player or together in Multiplayer.
Repair a shelter
Knock down 6 or more trees with 1 explosive. Alone in Single Player or together in Multiplayer.
In Single Player, don't kill any cannibals for more than 10 days in a row
Eat an enemy
Cut down 100 trees
Share a weapon in MP
Survive 5 nights
Make and wear stealth armour
Kill bird with arrow
Use the compass
Share a food or drink item in MP
Sleep with another player (group sleep)
Survive 1 night