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