Dry Ice Calculator

Dry ice (solid carbon dioxide) sublimates into fog when placed in warm water — popular for punch bowls and haunted entryways. This calculator multiplies your desired effect duration in minutes by an assumed consumption rate in pounds per hour, then divides by 60 for total pounds to purchase.

Burn rate depends on water temperature, chunk size, insulation, and airflow. Two pounds per hour is a common starting guess for small punch-bowl setups — raise it for outdoor bins or windy porches where sublimation accelerates.

Example: 30 minutes of fog at 2 lb/hour suggests buying about 1 lb of dry ice. Buy slightly more if the store sells fixed chunk sizes or if you want a stronger initial burst when guests arrive.

Carbon dioxide gas displaces oxygen in enclosed spaces — never use dry ice in sealed rooms, cars, or unventilated basements. The CDC and NIOSH publish carbon dioxide exposure guidance; this page does not compute safe indoor concentrations or ventilation requirements.

Handle with insulated gloves; do not touch bare skin. Do not seal dry ice in airtight containers — pressure buildup can rupture coolers. Keep out of reach of children and pets.

Retailers often will not sell to minors; transport in ventilated vehicles and use same-day for best fog — storage in home freezers is ineffective and can damage appliance seals.

Limits: heuristic purchase estimate only — not medical, occupational, or food-safety advice. Follow vendor instructions and local regulations for public events.