🫧 Priming Sugar Calculator
Enter your target carbonation, beer temperature, batch volume and sugar type to get the priming sugar to add at bottling.
Priming sugar
135.4 g
4.78 oz
CO₂ to add
1.54 vol
Already in beer
0.86 vol
Beer already holds dissolved CO₂ that depends on temperature — warmer beer holds less — so you only prime for the difference to your target. Use the highest temperature the beer reached after fermentation. Sugar factors are derived from CO₂ stoichiometry (corn sugar is dextrose monohydrate, so slightly more than table sugar by weight); published values vary a little. Dissolve the sugar in boiled water and mix gently to avoid oxidation. 🔒 In your browser.
How the priming sugar calculator works
Bottle carbonation works by feeding the yeast a measured dose of sugar so it produces exactly the CO₂ you want in the sealed bottle. The beer already holds some dissolved CO₂ that depends on its temperature, so the tool works out how much more you need and converts that to grams of your chosen sugar for the batch volume.
Use the highest temperature the beer reached after fermentation — that sets how much CO₂ is already dissolved (warmer beer holds less). Different sugars carry different amounts of fermentable weight, so corn sugar, table sugar and DME give slightly different doses; the factors here come from CO₂ stoichiometry and vary a little between references. Over-priming is dangerous — too much sugar can over-pressurise and burst bottles, so measure carefully.
Frequently asked questions
How much priming sugar do I need?
It depends on your target carbonation, beer temperature and batch size. For a typical 20 L ale to 2.4 volumes of CO₂ at 20 °C, it's roughly 120–130 g of corn sugar. Enter your figures for the exact amount.
Why does beer temperature matter for priming?
Beer already holds dissolved CO₂, and the amount depends on temperature — warmer beer holds less. You only add sugar for the difference between what's there and your target, so the temperature (the warmest it reached) sets the starting point.
What's the difference between corn sugar and table sugar for priming?
Both work; they just differ slightly by weight. Corn sugar (dextrose) is sold as a monohydrate so you need a touch more than table sugar (sucrose) for the same CO₂. The tool adjusts for the sugar you pick.
What carbonation level should I target?
By style: British ales around 2.0 volumes, American ales and lagers ~2.4, Belgian ales ~2.9, and wheat beers or saisons ~3.2 or higher. The tool has quick presets for these.
Can I add too much priming sugar?
Yes — and it's dangerous. Too much sugar over-carbonates and can build enough pressure to burst bottles ("bottle bombs"). Weigh the sugar accurately, don't guess, and never exceed what your bottles are rated for.