How to Fill a Co2 Canister With an Air Compressor

Oxygen image by JASON WINTER from

You can use compressed air/CO2 canisters for a variety of applications, from paintball guns and accessories to pellet rifles. However, getting the compressed air/CO2 canisters filled each time by a shop can become expensive. If you have a compressed air/CO2 tank fitting and an air compressor, you can easily fill the compressed air/CO2 tanks yourself and save considerable money.

Screw the compressed air/CO2 tank onto the compressed air fitting on the end of the compressor hose. Unscrew the bleed-off valve on top of the fitting to allow all of the leftover compressed air/CO2 to evacuate from the tank.

Close the bleed valve, then turn on the compressor. Fill the tank for approximately two seconds for each ounce of of compressed gas the tank will hold. For example, fill a 9-oz. tank for 18 seconds.

Turn off the compressor, and open the bleed valve for just a second or two to clean out the lines and make sure the tank valve closes properly. Unscrew the tank from the compressed air/CO2 tank adapter, and use it at your discretion.

Things You'll Need

  • Air compressor
  • Compressed air/CO2 tank
  • Compressed air tank fitting


  • Fill the tank only to capacity; overfilling it can blow a blast disc on your compressed air tank.