Here is the full list of all 27 Tabletop Simulator achievements. It takes around 200 hours to unlock all of the achievements on Windows.
Play a game with a full room of 8 players.
Play Tabletop Simulator for over 10 hours.
Tint 1000 objects a different color.
You posted a message in global chat, hurray!
Have two RPG figurines attack one another. They must hit!
Complete the tutorial in under 30 seconds.
Play a game in zero gravity.
Use your personal color page in the notebook.
Play a civilized game of Chess for 1 hour.
Play the game for 1 hour without flipping the table.
Play a game with someone on your friend's list
Complete the in-game tutorial.
Change your color more than 50 times.
Flip the table over 1000 times.
You tried to flip the table… and failed!
Flip the table in an absolute fit of rage… 100 times.
Spawn 10,000 poker chips!
Save 100 items to your Chest.
Create an 8 player “light show” with the line drawing tool.
Lock 5000 items over time.
You spawned the developers’ special figurines!
Upload at least 3 legitimate Steam Workshop items.
Play Tabletop Simulator for over 50 hours.
Play Tabletop Simulator for over 100 hours.
Play Tabletop Simulator for over 200 hours.
Play Tabletop Simulator for over 500 hours.
Play Tabletop Simulator for over 1000 hours.