Priming Sugar Calculator

About this calculator

Priming sugar is the measured amount of fermentable sugar — usually corn sugar (dextrose) or table sucrose — added to beer just before bottling so residual yeast can ferment it and produce the CO₂ that carbonates the beer naturally in the sealed bottle. The correct amount depends on the target carbonation level in volumes of CO₂ (typically 2.2–2.8 for most ale styles, higher for Belgian styles), the beer's volume, and critically the highest temperature the beer reached during fermentation, since warmer beer already holds less dissolved residual CO₂ and needs more priming sugar to reach the same final carbonation.

Homebrewers use this calculation on every batch before bottling day, since too little sugar leaves the beer flat while too much can over-carbonate bottles to the point of gushing or, in rare cases, bottle bombs.

This calculator takes your batch volume, the highest temperature the beer reached, and your target CO₂ volumes, then returns the precise amount of corn sugar or table sugar to add for safe, accurate carbonation.