Here is the full list of all 42 Gunpoint achievements. It takes around 6-8 hours to unlock all of the achievements on Windows.
Knock Fritz Gessler out of his office window.
Shoot Fritz Gessler.
Free an innocent man at the expense of catching a guilty one.
Create a custom mission with at least one objective.
Chicken out of telling Katie the truth at the last minute.
Beat Fritz Gessler to death.
Knock Fritz Gessler out with a punch.
Mock the chief of police at a critical moment.
Upgrade your battery capacity to the non-figurative max.
Notice the story doesn't necessarily gel with the mechanics. Become qualified games journalist.
Slam Fritz Gessler's office door into him.
Intimidate Fritz Gessler into surrendering.
Tell Gessler that Rooke's hired you to betray him.
Use the Prankspasm to knock out someone who isn't standing near a power socket (outside of the test lab).
Help justify my early, not entirely wise choice of game name by holding someone at gunpoint with the Resolver.
Complete a mission faster than I can.
Publish your personalised epilogue.
Complete the game.
Defeat Gessler by rewiring his gun.
Kick Fritz Gessler's office door into him.
Catch a guilty man at the expense of freeing an innocent one.
Use the Gatecrashers to kick a door off its hinges.
Use the Gatecrashers to kick a door into a guard.
Use the Gatecrashers to kick a door through a window.
Use the Hushcracker to jump through a window silently (outside of the test lab).
Jump into an Enforcer to knock him through a window.
Use the Longshot to make a guard unintentionally shoot another (outside of the test lab).
Steal Gessler's technology for Rooke.
Knock a guard out by opening a door into him.
Complete the police chief's missions without incriminating yourself.
Upgrade your Bullfrog Hypertrousers to pounce instantly.
Upgrade your Bullfrog Hypertrousers to maximum jump strength.
Conceal your presence at the DataSec break-in from Mayfield.
Voluntarily tell Katie the truth.
Get knocked down by an opening door.
Use the Dropshot to land silently from a great height.
Complete a mission that has guards with no violence, witnesses or loud noises.
Wire an elevator button to trigger something when the elevator arrives.
Use the Crosslink to create an infinite loop that burns itself out.
Leave no living witnesses to your presence on a mission that has guards.
This is an achievement in name only. No-one admires you for punching a guy that many times.
Use no violence at all on a mission that has guards.