Priming Sugar Calculator

Enter your batch size, the carbonation level you want in the bottle, and the warmest temperature the beer reached after fermentation. Get the exact weight of corn sugar, table sugar or DME to prime with.

Units
gal
vol

Volumes of CO2: ales usually 2.2-2.7, British ales 1.5-2.0, wheat beers 3.3-4.5.

°F

Residual CO2 depends on the warmest point the beer sat at after active fermentation, not the current temperature.

Value must be between 23 and 203.

Results

Value must be between 23 and 203.

How the calculation works

Finished beer keeps some CO2 from fermentation: the warmer it sat, the less remains. The calculator subtracts that residual CO2 from your target, then converts the difference to sugar: glucose yields about 0.49 g of CO2 per gram, sucrose about 0.51, and DME less because it is only partly fermentable.

Corn sugar (g) = (target volumes - residual volumes) × liters × 4.49; table sugar uses 3.85 per liter per volume

Want to bottle a known strength? Check the finished beer first with the ABV calculator, and if you measured warm or cold, fix the numbers with the hydrometer temperature correction tool.

Typical carbonation levels by style

Volumes of dissolved CO2 at serving. More volumes means more fizz - and more pressure in the bottle.

Style Volumes Notes
British ales 1.5-2.0 Cask-style, gentle fizz. Bold breweries bottle under 1.6.
American ales & lagers 2.2-2.7 Standard bottled beer feel.
European lagers 2.4-2.7 Pilsner-style crispness.
Belgian ales 2.6-3.2 Pronounced effervescence; use sturdy bottles.
Wheat beers 3.3-4.5 Hefeweizen foam. Pressure-rated bottles only.

Frequently asked questions

Why does a warmer fermentation mean more priming sugar?

CO2 stays dissolved in cold beer and escapes from warm beer. The calculator estimates how much CO2 your beer kept based on the warmest temperature it sat at after active fermentation: a beer that finished at 74 F retains far less CO2 than one at 60 F, so it needs more priming sugar to reach the same carbonation level.

Should I use corn sugar or table sugar?

Both work and taste nearly identical when used at normal priming rates. Sucrose (table sugar) is about 14% more efficient by weight, so you need roughly 10% less of it - the calculator accounts for this automatically. Corn sugar (dextrose) dissolves fastest and is the traditional choice; avoid powdered sugar with cornstarch additives.

What happens if I add too much priming sugar?

Over-carbonated bottles gush foam or, in extreme cases, can burst - standard 12 oz bottles are typically safe up to about 3 volumes of CO2. Stay within the style ranges in the reference table, use sturdy bottles for wheat or Belgian levels, and weigh the sugar rather than scooping it.

Can I prime my beer with honey?

Yes. Honey is roughly 80% fermentable sugars, so about 1.2-1.3 grams of honey per gram of corn sugar does the same job. Dilute it in a little boiled water first, and expect a faint honey character in delicate styles. The calculator covers the three most predictable priming sugars; honey varies a lot between batches.