Full list of all 63 Hollow Knight achievements. It takes around 60-80 hours to unlock all of the achievements in the base game on Windows.
The base game contains 52 achievements, and there are 3 DLC packs containing 11 achievements.
Leave Zote to die
Allow the Nailsmith to find a new calling
Achieve 100% game completion and finish the game in under 20 hours
Achieve 100% game completion and finish the game in Steel Soul mode
Complete the game in under 5 hours
Finish the game in Steel Soul mode
Complete the game in under 10 hours
Aid the Herald in moving on
Receive the Hunter's Mark
Record all of Hallownest's creatures in the Hunter's Journal
Achieve 100% game completion and finish the game
Complete the Trial of the Fool
Acquire all Mask Shards
Collect 2400 Essence and hear the Seer's final words
Bring peace to the Grey Mourner
Spend a final moment with Quirrel
Acquire all Charms and receive Salubra's blessing
Rescue all of the imprisoned grubs
Defeat the Radiance and consume the light
Defeat the Hollow Knight with Hornet by your side
Remember the past and unite the Abyss
Defeat the Hollow Knight and become the Vessel
Acquire all Vessel Fragments
Open all of Hallownest's Stag Stations and discover the Stag Nest
Collect 1800 Essence and awaken the Dream Nail
Defeat the Failed Champion
Defeat the Traitor Lord
Defeat the Soul Tyrant
Slay the Nailsmith with the Pure Nail
Complete the Trial of the Conqueror
Defeat the Collector
Acquire half of Hallownest's Charms
Acquire a map of each area
Destroy Monomon the Teacher
Collect 600 Essence
Complete the Trial of the Warrior
Defeat Zote in the Colosseum of Fools
Defeat Hornet in Kingdom's Edge
Rescue half of the imprisoned grubs
Defeat the Lost Kin
Destroy Herrah the Beast
Defeat the Mantis Lords
Destroy Lurien the Watcher
Acquire 3 Vessel Fragments
Defeat the Broken Vessel
Acquire 4 Mask Shards
Defeat the Soul Master
Defeat the Dung Defender
Open half of Hallownest's Stag Stations
Defeat Hornet in Greenpath
Acquire your first Charm
Defeat the False Knight
Defeat Grey Prince Zote
Defeat White Defender
Banish the Grimm Troupe from Hallownest
Defeat the Nightmare King and complete the Ritual
Defeat Troupe Leader Grimm
Ascend the Pantheon of Hallownest and take your place at its peak
Achieve 112% game completion and finish the game.
Complete the Pantheon of the Knight
Complete the Pantheon of the Sage
Complete the Pantheon of the Painter
Complete the Pantheon of the Master