Champagne Headspace Pressure Calculator

Every time you open a bottle, pour a glass, and recap it, some dissolved CO₂ leaves the wine to fill the enlarged headspace. This calculator lets you explore exactly how much. The same physics applies to Champagne, sparkling wine, soda, beer, and any other carbonated beverage.

In the calculator below, you start with a full bottle of Champagne at 40 F and 65 psi pressure of CO₂ in the headspace. Pour a glass and recap the bottle, and see what the new equilibrium pressure will be. Hint: it will be lower. 

Notice what happens? Every pour vents the headspace CO₂, decreases the amount of Champagne left, and increases the headspace. So, with each pour, the CO₂ in the headspace is lost, and there's a bigger headspace to fill, and there's a smaller reservoir of Champagne to fill it from. It's a triple whammy. 

And that's why the Perlage System is better than a cap or a stopper. Perlage puts the CO₂ back in the headspace where it belongs. 

Things to Try

Experiment 1 - Pour a glass: Set your pour to 5 ounces, and click Pour & Recap. Note the new equilibrium pressure. 

Experiment 2 - Don't pour anything: Now pour zero ounces; that is, set the amount to pour to zero. Click Pour & Recap. This is equivalent to just taking the cap off and putting it back on without pouring. What happens to the new equilibrium pressure? 

Experiment 3: One big pour or two small pours? Compare the following. First pour a 5 ounce glass, and then pour another 5 ounce glass. Note the final equilibrium pressure. Reset the calculator. Now make one 10 ounce pour. Which loses the most CO₂?

Still Curious?