Dry Ice Calculator
Choose a cooler or a freezer that is not working and how long you need. You get the pounds and kilograms of dry ice as a range from published rates.
How to use the Dry Ice Calculator
- Under “What are you keeping cold?”, choose “A cooler (5 to 10 lb lost per 24 h)” or “A freezer that is not working”.
- Under “How long”, enter how long you need the ice to last, in hours or days. The default is 2 days.
- If you chose a freezer, pick the “Freezer type”: “Freezer on the bottom”, “Freezer on top”, “Side-by-side”, or “Chest freezer”.
- Read “Dry ice to buy”, the pounds range. For a cooler, it is days × 5 lb to days × 10 lb. For a freezer, it is the per-24-hour figure for that type, multiplied by the days.
- Read “In kilograms”, the same range in kilograms.
- In freezer mode, check the table of the four freezer types, with their pounds per 24 hours from the university EHS guideline.
- Note the “USDA FSIS reference”, which says 50 pounds should hold an 18-cubic-foot full freezer for 2 days. It is shown for reference only and is not used in the calculation.
- Read “Safety” and “Shipping” before you buy or handle the ice, and read the warnings under the result.
To start quickly, use a preset: “Cooler, 1 day”, “Cooler, 2 days”, “Cooler, 3 days”, or “Chest freezer, 2 days”. Presets fill in the inputs for a common case, and you can change any input afterward. Part-day times are scaled in proportion, so 36 hours counts as 1.5 days.
How does the dry ice calculator work out the amount?
The calculator multiplies the number of days by a published rate per 24 hours and gives the answer as a range. For a cooler, the formula is days × 5 lb to days × 10 lb. That rate comes from a Notre Dame lab procedure and Florida International University EHS, which give a loss of 5 to 10 lb every 24 hours in a typical storage cooler.
Part-days are scaled in proportion, so 36 hours is 1.5 days. None of the sources confirms this method for part-days, so treat that number as an estimate and plan for the upper end of the range.
How much dry ice do I need for a cooler?
Use days × 5 lb to days × 10 lb. A cooler for 2 days needs 10 to 20 lb, which is 4.54 to 9.07 kg. Twenty-four hours needs 5 to 10 lb, and 3 days needs 15 to 30 lb.
Cooler size and outside temperature are not modelled. No public source gives a rule for them. A big or poorly insulated cooler may need more than the range shows, so the calculator warns about this. Above 7 days, it also asks you to check the ice regularly.
How much dry ice do I need for a freezer that is not working?
Florida International University EHS gives amounts per 24 hours: a freezer on the bottom needs 15 to 25 lb, a freezer on top 20 to 30 lb, a side-by-side 30 to 40 lb, and a chest freezer 40 to 50 lb. Multiply the figure for your type by the number of days. A chest freezer for 2 days needs 80 to 100 lb, a freezer on the bottom for 1 day needs 15 to 25 lb, and a side-by-side for 3 days needs 90 to 120 lb.
USDA FSIS, in Preparing for a Weather Emergency (2008), says 50 pounds of dry ice should hold an 18-cubic-foot full freezer for 2 days. This is a different statement from the Florida International University figures: for a chest freezer, FIU gives 40 to 50 lb per 24 hours, or 80 to 100 lb for 2 days, while USDA FSIS gives 50 lb for an 18-cubic-foot full freezer for 2 days. The calculator shows it as a reference and does not combine it with the range, so compare the two without adding them together.
The calculator does not decide whether your food is safe. Your local health department adopts its own code edition and may be stricter than the FDA Food Code or USDA guidance.
Sources (checked 15 October 2026): www3.nd.edu · ehs.fiu.edu · sbcounty.gov · fsis.usda.gov · nist.gov
Worked examples
| Input | Result |
|---|---|
| a cooler, 2 d | 10 to 20 lb |
| a cooler, 1 d | 5 to 10 lb |
| a freezer, 1 d | 15 to 25 lb |
| a freezer, 2 d | 80 to 100 lb |
Calculated by the tool above; open it with the same values to see each step.
Frequently asked questions
Is the dry ice calculator free to use?
Yes. It runs in your browser and is free. Nothing you enter is uploaded, so your numbers stay on your device.
How much dry ice for a cooler for 3 days?
A cooler for 3 days needs 15 to 30 lb, based on 5 to 10 lb per 24 hours. The “cooler 3 days” preset fills this case in for you.
What if I need dry ice for more than 7 days?
Above 7 days, the calculator shows a warning asking you to check the ice regularly. The estimate is not meant for that length of time, so check the dry ice and the food regularly instead of relying on it.
Can I take dry ice on a plane?
Dry ice is regulated for shipping and air travel, and each carrier has its own rules. Ask the carrier before you travel or ship dry ice.
Should I handle dry ice with my bare hands?
No. Use insulated gloves, and keep dry ice out of direct contact with food, as USDA FSIS advises. Use it in open or ventilated places, never in an airtight container. Pick it up close to when you need it.
Does the calculator tell me whether my food is safe?
No. It gives an amount of dry ice only. Your local health department adopts its own edition of the code and may be stricter than the FDA Food Code or USDA guidance, so check with them about local rules.
Related tools
- How Long Does Dry Ice Last?: Use it when you want to know how long dry ice keeps working, not just how much to buy.
- Kegs and Coolers: the hub page for all keg and dry ice tools.
- Food Temperatures and Holding: pages on keeping food cold.
- Cold Chain Monitoring: use it when cold goods travel between places.
- How Many Beers in a Keg?: use it to count servings when the cooler holds drinks.
- Keg Sizes: use it to compare keg volumes.
- Food Danger Zone: read it for the temperature range where food needs care.