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