Priming Sugar Calculator
Bottle carbonation is all about dosing the right amount of sugar. Enter your packaging volume, sugar type, beer temperature, and target carbonation, and get the exact priming sugar to reach it — with the estimated total CO2 and the safety points that matter when bottles hold pressure.
Use the actual volume going into bottles and the highest temperature the beer reached after fermentation — that sets the CO2 already dissolved.
Typical ranges: British ales 1.5–2.2, American ales 2.2–2.7, wheat & Belgian 3.0–4.5. Higher targets mean more pressure.
Formula & how it works
The CO2 already dissolved is estimated from temperature: residual = 3.0378 − 0.050062·T + 0.00026555·T² (T in °F). The CO2 to add is target − residual in volumes.
Sugar is K × liters × (target − residual), where K is grams per liter per volume of CO2: about 4.41 for corn sugar, 3.81 for table sugar, and 6.79 for dry malt extract.
Worked example
Five gallons (18.9 L) of beer at 68 °F already holds about 0.86 volumes of CO2. To reach 2.4 volumes you need to add 1.54 volumes, which is roughly 128 g (about 4.5 oz) of corn sugar. The same target with table sugar takes about 111 g, or about 198 g with dry malt extract.
Getting carbonation right
Match the target to the style
Different styles carbonate to different levels. English ales are often gently carbonated, American ales sit a little higher, and wheat and Belgian styles can be quite lively. Choosing a target that suits the beer matters not just for taste but for safety — higher volumes mean more pressure in the bottle.
Temperature sets the starting point
Beer already contains dissolved CO2, and how much depends on the warmest temperature it reached after fermentation. Warm beer has vented more, so it needs more sugar; cold beer retains more and needs less. Using the right temperature is the difference between flat bottles and dangerously over-primed ones.
Bottle only finished beer
The single most important rule is to bottle only when fermentation is truly done and gravity has stopped moving over several days. Priming assumes the yeast will ferment just the sugar you added; if the beer was still fermenting, that extra sugar becomes extra pressure. When in doubt, wait and take another gravity reading.