How To Carbonate Homebrew In a Corny Keg: Carbonating Your Beer 5 Different Ways

Mar 2021 | Last modified: November 14, 2023 | 9 min read | By David Scott

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How To Carbonate Your Homebrew Without Losing Your "Head"

Bottling is a pain. It’s also messy, laboring, and requires a lot of time.

When you decide to brew beer, you quickly realize that bottling all those beers isn’t going to be fun, but it doesn’t have to be that way! A much better way is to package and carbonate your beer in a keg.

There are 5 different ways you can carbonate your homebrew in a keg, and each one has its own pros and cons.

Reasons For Carbonating Beer In a Keg

It could take a few days or a few weeks to carbonate, depending on the type of beer, but it’s well worth it. There are quite a few reasons why you should let your homebrew carbonate in a keg.

  • Faster alternative to bottling
  • Simple to do
  • Better control over the level of carbonation
  • More consistent pour
  • Better head retention
  • CO2 protects beer from oxygen

What Equipment Do You Need?

Force carbonating your beer requires time, temperature, and the correct pressure, so carbonating your beer in a keg will require a few additional pieces of equipment before you get started.

  • Keg
  • Filled CO2 tank
  • Regulator
  • Gas/liquid hoses and connectors
  • Dispensing system
  • A place to keep the keg cold (kegerator, refrigerator, keezer)
  • Force carbonation chart
If you haven’t kegged your beer yet, check out our “How To Keg Your Homebrew” page, where you’ll find a more detailed and in-depth explanation of the items you need, how to clean and sanitize the keg, along with the complete kegging process.

5 Ways To Carbonate Homebrew In a Keg

These are the 5 different ways to carbonate your homebrew when kegging.

  • Set it and forget it
  • Shake it
  • High-pressure CO2 burst
  • Quick Carb
  • Natural

Set It and Forget It

With the “set it and forget it” method, the CO2 is pumped into the keg at the serving pressure of 12 – 15 psi, which will slowly carbonate the beer over a longer period of time, compared to other methods.

A pressure of 12 to 15 psi is usually an optimal serving pressure, depending on where you live. The optimal serving pressure is 12 psi, if you are at sea level. For every 1000 feet above sea-level, add an additional 1/2 psi.

So turn the gas on, adjust the regulator between 12 and 15 psi, and cold crash the keg in a kegerator or refrigerator while it is under pressure, and let it ride until it is carbonated.

Depending on the style of beer, this will probably take between 7 and 14 days for the beer to fully carbonate. Go ahead and take a sample sip after 4 or 5 days to get a better idea of the carbonation level.

Although you need to have some patience, this low and slow method is probably the easiest and the most consistent of all.


  • Simple to do
  • Consistent results
  • Very little risk of over-carbonation
  • Gives time for sediment to settle at the bottom of the keg


  • Takes the most time of all force carbonation methods

High Pressure CO2 Burst

The force carbonation method will carbonate your beer faster than “set it and forget it” shown above. There is a much higher chance of over-carbonation, but the trade-off is getting to drink your beer much sooner.

Feed the keg with a higher amount of CO2 between 30 and 40 psi for 12 to 24 hours. The higher the pressure, the faster the beer will carbonate.

After a day or so, purge the keg. then reduce the pressure to your desired serving pressure.


  •  Ready to drink sooner than “set it and forget it”


  •  Risk of over-carbonation

Shake It Up

If you are too impatient and want to get the job done much quicker, try one of these two shaking techniques instead.  With the “shake it” method, you will be able to drink a nice carbonated beer in much sooner, and get a nice workout in at the same time.

Shaking the keg will get more of the CO2 bubbles in suspension, while agitating the beer, which will give more surface area for the CO2 to contact the beer.

Method #1

Connect the gas line to the keg and adjust the CO2 pressure to 30 psi.  You can then pick the keg up and just shake it for about 5 minutes. It will be easier if you lay it floor and roll it back and forth.  Laying the keg horizontally will even create a larger surface area for the CO2 to make contact with the beer.

After your workout, put it back in the refrigerator for 30 to 45 minutes for the beer to settle down. Then pull up on the pressure relief valve to purge the tank. Reconnect the gas line, and fill the keg with a 10 to 12 psi serving pressure before checking the carbonation.

Method #2

You will still shake the keg to agitate the beer, but it is done with a lower pressure for a longer period of time.

Connect the gas hose and set the regulator to your preferred serving pressure for the type of beer you are carbonating, which will be somewhere between 8 and 15 psi.

While the keg is cold crashing, give the keg a few good shakes throughout the day.  Do this for 3 or 4 days, but do not shake the keg the day before you plan on serving.


  • Will carbonate the beer much faster


  • Unreliable results
  • More effort is required
  • Over-carbonation risk

Quick Carb Pump

Using a quick carb pump system will have your beer carbonated and ready to drink in less than 60 minutes when you follow a recommended carbonation chart that is based on the type of beer and temperature.

This force carbonation method uses a small recirculating pump with a stainless steel diffusion stone, without the chance of over-carbonating your beer.

Although the beer will be 90% carbonated in under an hour, you still need to let the keg rest for a few hours to get an accurate carbonation level.


  • Ready to drink in under an hour
  • Works with all beer styles


  • Most expensive method
  • More equipment to clean and sanitize

Priming Sugar

You can also naturally carbonate the beer in a keg, just like bottling, but you will still need to use CO2 to check for leaks, seat the lid, and serve the beer.

Just like adding a priming sugar solution to a bottling bucket before bottling, you add the priming solution to the keg before racking the beer on top of the priming solution.

The amount of priming sugar needed will depend on the amount of beer, the type of beer, and the desired amount of CO2 you want in the finished beer. Be sure to use an online priming sugar calculator for the amount of beer, the beer temperature, and the CO2 volume.

Add the sugar to the water and boil for 5 minutes, then pour the sugar/water mixture in the sanitized keg. Use an auto-siphon to transfer the beer to the keg, then attach the lid. Place the keg in a cool place (68° – 72°) for about 2 weeks.

After 2 weeks, cool the keg in a refrigerator or kegerator and chill to serving temperature before pressurizing with CO2 to the optimal serving pressure.


  • Can carbonate outside of the refrigerator or kegerator
  • Allows time for conditioning
  • Some brewers claim a better mouthfeel to the finished beer


  • Can take up to 2 weeks to fully carbonate
  • More sediment is possible in the keg

How Does Temperature Effect Carbonation?

The temperature of the beer has a direct affect on the carbonation process.

Aside from naturally carbonating in a keg, any force carbonation using CO2 should be done with cold beer, by cold crashing in a refrigerator, keezer, or kegerator first.

The lower the temperature of the beer is, the faster the carbon dioxide will dissolve into the beer. Also, that means less CO2 pressure will be needed when force carbonating the beer.

Why Is My Kegged Beer Flat?

Is your beer still flat after force carbonating? More than likely, you have a leak somewhere in your kegging system, or maybe the lid on the keg is not seated.

While under pressure, look for bubbles by spraying a solution like Star San on all the parts. Check all components for leaks, including the regulator, hoses, keg posts, connectors, and the lid. Also make sure the gaskets and o-rings do not need to be replaced.

Why Is My Beer Over-Carbonated?

There are a few reasons why your beer can be carbonated.

The first thing to check is the CO2 pressure. Too much pressure can be the cause of too much foam when coming out of the tap. Purge the keg and give the beer a rest and time to settle down in the refrigerator.

Not all beer serving pressures are created equal. Use this carbonation chart to get the right psi and temperature for your style of beer.

Can I Re-Carbonate Flat Beer?

Yes you can re-carbonate your flat beer coming out of the keg.

If you are force carbonating using CO2, just follow one of the methods listed above. Just don’t forget to purge the excess headspace from the keg.

Did you use priming sugar to naturally carbonate the beer? Using a sugar solution can be used again, but the amount of sugar used will be different if the amount of beer is different.  If you can determine how much beer is left in the keg, use this priming calculator for the correct amount.

Final Say

Whether you want to force carbonate, or naturally carbonate your beer, there are quite a few options to choose from, and each method comes with both advantages and disadvantages.

Any one of the 5 ways to carbonate your beer in a keg will work, it just depends on how quick you want to drink the beer.

Homebrewing is always about experimenting and trying to make the perfect batch of beer.  Finding the best carbonation technique for the perfect pour can also be an experiment too.

There is no right or wrong way, and every homebrewer has their own preference for one reason or another, and you will too.

Happy Brewing!

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