Priming Sugar Calculator for Homebrewing

By Dan Smullen

Priming sugar is what carbonates your beer in the bottle. Add too little and it pours flat, add too much and you risk gushers or broken glass. Enter your batch details below for the exact weight you need.

Calculate your priming sugar

How to read your result

The main figure is the sugar weight to add to the whole batch at bottling. Dissolve it in a little boiled water, cool it, and gently mix it through the beer before you fill the bottles so every bottle carbonates evenly.

Give bottle conditioning about two weeks at room temperature before you chill and test one. If it is undercarbonated, the beer may just need more time and warmth rather than more sugar.

Why beer temperature matters

Warm beer holds less dissolved CO2 than cold beer, so it needs more sugar to reach the same carbonation. The temperature that counts is the highest the beer reached after fermentation, not the temperature on bottling day, because that is what set the CO2 already in solution.

Pick your target CO2 volumes to suit the style: British ales around 1.8 to 2.2, American ales 2.2 to 2.7, and wheat beers and lagers higher. The calculator does the rest.

Frequently asked questions

Why does beer temperature matter for priming?

Warm beer holds less dissolved CO2 than cold beer, so it needs more priming sugar to reach the same carbonation. Use the highest temperature the beer reached after fermentation, not the temperature on bottling day, because that is what set the residual CO2 already in solution.

How many CO2 volumes should I aim for?

Most British ales sit around 1.8 to 2.2 volumes, American ales 2.2 to 2.7, and lagers and wheat beers 2.4 to 3.0. Pick the target for your style and the calculator gives you the sugar weight.

Can I swap corn sugar for table sugar?

Yes. Table sugar (sucrose) carbonates slightly harder per gram than corn sugar, so you need a little less of it. Choose your sugar type and the calculator adjusts the weight for you.

More homebrewing calculators

This is one tool in the full homebrewing suite. Whatever stage of the brew you are at, there is a calculator for it.

ABV CalculatorTurn your original and final gravity into alcohol by volume, with a high-gravity toggle.IBU CalculatorEstimate bitterness from hop weight, alpha acid, boil time and batch size using the Tinseth method.Priming Sugar CalculatorWork out the exact priming sugar for bottle conditioning from batch size, target CO2 and beer temperature.Strike Water CalculatorFind the strike water temperature to hit your mash target, plus an optional mash, sparge and total water plan.Carbonation CalculatorFind the regulator pressure to force carbonate your beer to a target CO2 level at a given temperature.Keg Carbonation CalculatorSet the right keg pressure for your beer style and serving temperature so it pours perfectly carbonated.Mash Efficiency CalculatorMeasure your brewhouse efficiency by comparing the gravity you hit against the maximum your grain bill could give.Yeast Pitch Rate CalculatorWork out how many yeast cells your batch needs from its gravity, volume and whether it is an ale or a lager.Hydrometer Temperature Correction CalculatorCorrect a hydrometer reading taken at the wrong temperature back to an accurate specific gravity.Original Gravity CalculatorCorrect your original gravity reading for temperature so your OG and later ABV are accurate.Final Gravity CalculatorCorrect your final gravity reading for temperature to know when fermentation is truly finished.Beer Recipe CalculatorScale every ingredient in a recipe up or down to a new batch size, keeping the balance intact.Batch Size CalculatorResize a recipe to your kettle or fermenter by finding the scale factor between two batch sizes.Beer Calories CalculatorEstimate the calories, alcohol and carbs in a serving of beer from its original and final gravity.Beer Line Length CalculatorWork out how much beer line you need for a balanced kegerator or draft system, based on your regulator pressure, rise and tubing size.

All homebrewing calculators