How cold is dry ice?

To remain in its solid phase, dry ice must be kept at temperatures lower than -109.3 degrees Fahrenheit. At higher temperatures, dry ice begins to sublimate, or turn directly from a solid into a gas.

Dry ice is solid carbon dioxide, which exists as a trace gas in Earth's atmosphere and only becomes a solid at temperatures below -109.3 degrees. Aside from absolute zero, no lower limit exists for the solid phase of carbon dioxide, so dry ice can be maintained at any temperature under its sublimation point. Carbon dioxide does not enter a liquid phase at normal air pressure, so it cannot be cooled below its freezing point without forming ice.