Tool
Is this bottle going to be safe?
The pressure a given carbonation level reaches at a given temperature, against what common closures and bottles will actually hold.
Bottle pressure
Pressure rises steeply with temperature. Check the warmest place the bottle will sit, not the coolest.
Pressure in the bottle
1.9 bar
In psi: 28 psi
This is an estimate from a model, not a measurement.
How this is worked out
- Carbonation: 2.50 volumes of CO₂
- At temperature: 20.0 °C
- Gauge pressure: about 1.9 bar (28 psi)
What this assumes (4)
- Pressure rises steeply with temperature. A bottle that is comfortable in a cold cellar can be at twice the pressure in a warm room, which is why over-carbonated bottles fail in summer rather than in winter.
- A crown-capped beer bottle is generally rated to around 4 bar; a Champagne bottle to considerably more; a still-wine bottle is not a pressure vessel at all.
- This figure is for the temperature you entered. Pressure rises steeply with warmth, so a batch that is comfortable here can be past a closure rating in a hot room — check it at the warmest temperature the bottles will ever reach rather than at the one they are at now.
- This is an approximation intended to show whether a figure is near a limit, not a certification of any particular container.
What the numbers mean in practice
A crown-capped beer bottle is generally treated as safe to around 4 bar. A Champagne bottle is built for considerably more and is the right container for a traditional-method cider. A still-wine bottle is not a pressure vessel at all, and carbonating in one is the single most common way home producers get hurt.
Pressure rises steeply with temperature, which is why over-carbonated bottles fail in summer rather than in winter. Work from the warmest place the bottles will actually sit, not the cellar you are storing them in today.
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