Cider Priming Sugar Calculator
Enter your batch size, carbonation style and conditioning temperature
Next step: Check your cider's ABV from original and final gravity.
Cider ABV Calculator →How Priming Sugar Works
A finished dry cider is a good candidate for bottle conditioning because the yeast that fermented it is still alive and hungry. Seal a measured dose of sugar into the bottle with it and the CO2 from that last small fermentation has nowhere to go but into the cider. The dose sets the fizz: a farmhouse cider wants barely more than a prickle, a modern sparkling cider wants beer-level carbonation, and a champagne-method cider wants more than a swing-top bottle can safely hold.
Cider fermented cool in autumn and racked in a cold cellar still holds a good deal of CO2 from primary, which is why a cold-stored cider can taste faintly spritzy from the cask. That residual gas counts toward the target. The calculator estimates it from the warmest temperature the cider reached after fermentation ended, because that is the point where the most gas escaped, then adds only the difference.
The three options shown are alternatives, not a combined dose. Corn sugar (dextrose monohydrate) and table sugar (sucrose) are both nearly fully fermentable; corn sugar needs slightly more by weight because of the water bound into its crystal structure. Apple juice concentrate is a popular natural alternative among cidermakers, but its exact sugar concentration varies by brand (commonly 65-70 Brix), so treat the calculated figure as a starting point and taste-test a small batch first.
Carbonation Targets for Cider and a Worked Example
| Style | Target volumes CO2 | Notes |
|---|---|---|
| Still or petillant farmhouse | 1.0 to 1.5 | Often none: residual CO2 from cold storage is enough |
| English draught style | 1.5 to 2.2 | Light dose, crown-capped beer bottles |
| Modern sparkling cider | 2.5 to 3.0 | Standard dose, beer or cider bottles |
| New England or hopped cider | 2.8 to 3.2 | Standard to firm dose, beer bottles |
| Champagne-method cider | 3.5 to 4.5 | Champagne bottles and cages only |
Worked example. 19 litres of dry cider, warmest storage temperature 18°C, target 2.7 volumes for a modern sparkling cider. The residual CO2 curve this calculator uses gives 0.92 volumes already dissolved at 18°C, so 2.7 − 0.92 = 1.78 volumes must come from the priming sugar. At 1.9647 g of CO2 per volume per litre and 2.25 g of corn sugar per gram of CO2, that is 1.78 × 19 × 4.42 = 150 g of corn sugar, or 129 g of table sugar, or about 205 g of apple juice concentrate at 70 Brix. Had the cider sat at 22°C instead, the residual drops to 0.81 volumes and the corn sugar dose rises to 158 g: a difference worth entering the temperature for.
Sweet and Sparkling: The Decision Beer Makers Never Face
Cider brings a problem beer does not have. Bottle conditioning needs live yeast and a dry base, but most drinkers prefer cider with some sweetness, and any sugar left in a bottle with live yeast will keep fermenting until the bottle fails. You cannot have all three of sweet, sparkling and bottle-conditioned without an intervention.
The workable routes: prime a dry cider and accept it dry, which is what this calculator does. Back-sweeten a stabilised cider with sorbate and sulphite and carbonate it with force in a keg, since stabilised cider will not bottle-condition. Bottle-pasteurise a primed, back-sweetened cider once it reaches carbonation, which needs a thermometer, a test bottle and care. Or keeve, the traditional French method that starves the yeast of nutrients so it stops naturally with sugar remaining, giving a naturally sweet petillant cider at the cost of yield and predictability. The back-sweetening and stabilising calculator covers the sorbate and sulphite doses for the second route.
Whichever route you take, the rule is the same: never prime a cider that still holds fermentable sugar. Two identical hydrometer readings three days apart are the minimum proof it is finished.
Avoiding Over-Carbonation
Over-priming is a genuine safety issue, not just a quality one. Excess CO2 pressure inside a sealed glass bottle can cause it to fail, sometimes violently. This risk is worth taking seriously with cider specifically, since dry cider left with any unfermented residual sugar can carbonate further than expected once bottled if fermentation was not genuinely complete. Always weigh priming sugar on a scale rather than estimating by volume with a spoon or cup.
Use bottles actually rated for carbonation, such as proper beer or cider bottles or swing-top bottles designed for pressure, never single-use wine or juice bottles. Store conditioning bottles somewhere they can be safely contained if one does fail, and never add extra sugar beyond a calculated dose on the assumption that more carbonation is simply better.