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Carbonation Calculator

Dial in the perfect fizz — force-carb PSI for kegs or priming sugar for bottles, adjusted for your beer style and temperature.

CO2 volumes determine how lively your beer feels in the glass — a Hefeweizen needs twice the carbonation of a West Coast Stout.

For kegs, the right serving pressure depends entirely on temperature: beer at 38°F holds far more gas than beer at 55°F, so the same 2.5 volumes might need 12 PSI or 22 PSI.

For bottles, you add a measured dose of priming sugar that the remaining yeast ferments into CO2. Too little leaves a flat beer; too much risks bottle bombs.

1. Choose Your Beer Style

Target CO2 range: 2.2 - 2.7 volumes

Balanced fizz that does not overpower malt or hops.

2. Target Carbonation

2.4
1.0 (still)5.0 (champagne)

3. Beer Temperature

4. Carbonation Method

Keg Force Carbonation

10.2

PSI at 38°F / 3°C

~14

Days (set & forget)

Regulator Pressure

0 - 30 PSI

Set your regulator to 10.2 PSI at 38°F and leave it connected. For faster results, burst at 30 PSI for 24-48h, then drop to 10.2 PSI.

💡 Why temperature matters

CO2 dissolves into cold liquid far more readily than warm liquid. The colder your beer, the lower the pressure needed to reach a given carbonation level. If you carbonate cold then warm the keg to serve, the beer can foam violently — always calculate PSI at the actual temperature the beer will sit at.

📋 Carbonation Cheat Sheet

  • • British ales & stouts: 1.5-2.3 volumes (low, smooth)
  • • American ales & lagers: 2.2-2.8 volumes (medium-high)
  • • German wheat & Belgian: 3.0-4.5 volumes (very high)
  • • Cold beer needs less pressure than warm beer for the same fizz

Frequently Asked Questions

How do I know the right CO2 volume for my beer?
Each beer style has a traditional carbonation level measured in 'volumes of CO2.' A West Coast stout sits around 1.7-2.3 volumes for a smooth, low-fizz pour, while a Hefeweizen needs 3.3-4.5 volumes for its lively, foamy character. This calculator gives you the target range for 20+ styles.
Why does temperature matter for force carbonation?
Cold beer holds CO2 far more easily than warm beer. At 38°F a keg reaches 2.5 volumes at about 12 PSI, but at 55°F you would need roughly 22 PSI for the same carbonation. Always calculate PSI at your beer's actual serving or carbonating temperature.
How much priming sugar should I use for bottles?
It depends on your batch volume, target CO2 volume, and the residual CO2 already in the beer (which is set by fermentation temperature). For a typical 5-gallon ale targeting 2.4 volumes, you need roughly 110-130g of dextrose. This tool computes the exact weight for dextrose, table sugar, or DME.
Can I over-carbonate and create bottle bombs?
Yes. Adding too much priming sugar produces excess CO2 that can shatter bottles. Stay within the style's range, use the calculated amount, and never exceed about 3.5 volumes in standard glass bottles unless they are rated for high pressure (like Belgian or champagne bottles).
How long does force carbonation take?
At set-and-forget serving pressure, a cold keg reaches full carbonation in 1-2 weeks. The 'burst' method (cranking to 30+ PSI for 24-48 hours, then dropping to serving pressure) is faster but riskier to over-carbonate. This calculator estimates days to carb at your chosen pressure and temperature.

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