Full list of all 63 Battlefield 3 achievements worth 1,600 gamerscore. It takes around 40-50 hours to unlock all of the achievements in the base game.
The base game contains 38 achievements worth 1,000 Gamerscore, and there are 5 DLC packs containing 25 achievements worth 600 Gamerscore.
Completed all co-op missions on Hard
Reached the garage without going into man-down state in Hit and Run
Reached the VIP without setting off the alarm in Exfiltration
Completed the mission without losing a humvee in Operation Exodus
Saved the hostages without alerting any enemies in Drop 'em Like Liquid
Received one of each ribbon in the game
Rank 45 achieved!
Completed the campaign story on Hard
Received all 3 vehicle warfare ribbons
Took down the jet in one attempt in Rock And A Hard Place
Received all 4 support efficiency ribbons
3rd MVP in a ranked match
MVP in a ranked match
2nd MVP in a ranked match
Completed the street chase in Comrades in under 2 minutes 30 seconds without dying
Completed Going Hunting in a perfect run
Received all 4 weapon efficiency ribbons
Killed the 2 soldiers before the building fell on them in Uprising
Kicked the car and killed the soldiers in Uprising
Completed the campaign story
Beat Solomon, flawlessly, in The Great Destroyer
Captured Kaffarov
Headshot each of the targets in the gun range in Kaffarov
Took a Russian Dog Tag in the forest ambush in Rock And A Hard Place
Took down 2 enemies with 1 bullet in Night Shift
Captured Al Bashir
Shot out the 4 lights with 4 bullets in Night Shift
Took your first enemy Dog Tag
Unlocked all unique co-op weapons
Completed all co-op missions
Disarmed the bomb in under 20 seconds in The Eleventh Hour
Destroyed 6 enemy tanks before reaching the fort in Thunder Run
Failed to prevent the attack
Found the nuke
Survived the quake
Protected Chaffin from the soldiers in the street in Operation Swordbreaker
Completed the mission without using the fire extinguisher in Fire From The Sky
Completed Semper Fidelis
Got 10 kills with each of the ten Back to Karkand weapons
Got a kill with each of the following vehicles: the BTR-90, DPV and F-35.
Got a kill with the following weapons in a single life: Assault Rifle, Jet, Tank
Got a kill with the skid loader
Took a swim in the Oman Hotel swimming pool
Got 10 kills with all ten CQ weapons
Fell over the edge on Ziba Tower
Without dying, got a kill with a Carbine, Pistol and Rocket Launcher
Completed a round of Gun Master
Won a round in Conquest Domination
Got 10 kills each with Tank destroyers and Mobile Artilleries
Won one round of Tank Superiority
Got one kill with the Quad bike
Destroyed the Gunship
Got one kill with the Gunship
Without dying, got a kill with xbow, primary weapon, and hand grenade
Unlocked all xbow parts
Destroyed an enemy vehicle using the xbow
Found the secret reptile
Picked up 50 weapons in Scavenger mode
Got a kill from the passenger position on a motorcycle
Transported a flag carrier in an air vehicle in CTF
Killed an enemy after successfully paradropping a vehicle
Captured one flag while playing CTF
Destroyed an air vehicle using the AA jeeps