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.
Defeat Gessler by rewiring his gun.
Catch a guilty man at the expense of freeing an innocent one.
Create a custom mission with at least one objective.
Notice the story doesn't necessarily gel with the mechanics. Become qualified games journalist.
Kick Fritz Gessler's office door into him.
Slam Fritz Gessler's office door into him.
Beat Fritz Gessler to death.
Intimidate Fritz Gessler into surrendering.
Shoot Fritz Gessler.
Tell Gessler that Rooke's hired you to betray him.
Mock the chief of police at a critical moment.
Chicken out of telling Katie the truth at the last minute.
Voluntarily tell Katie the truth.
Use the Prankspasm to knock out someone who isn't standing near a power socket (outside of the test lab).
Jump into an Enforcer to knock him through a window.
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.
This is an achievement in name only. No-one admires you for punching a guy that many times.
Use the Longshot to make a guard unintentionally shoot another (outside of the test lab).
Publish your personalised epilogue.
Complete the game.
Knock Fritz Gessler out with a punch.
Use the Gatecrashers to kick a door through a window.
Use the Gatecrashers to kick a door into a guard.
Use the Gatecrashers to kick a door off its hinges.
Free an innocent man at the expense of catching a guilty one.
Complete the police chief's missions without incriminating yourself.
Upgrade your battery capacity to the non-figurative max.
Upgrade your Bullfrog Hypertrousers to maximum jump strength.
Conceal your presence at the DataSec break-in from Mayfield.
Steal Gessler's technology for Rooke.
Use the Hushcracker to jump through a window silently (outside of the test lab).
Knock a guard out by opening a door into him.
Get knocked down by an opening door.
Use the Dropshot to land silently from a great height.
Upgrade your Bullfrog Hypertrousers to pounce instantly.
Leave no living witnesses to your presence on a mission that has guards.
Use no violence at all on a mission that has guards.
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.