How Much Ice for 100 People

For 100 people over 3 hours at 80°F with cold drinks, buy 145 lb of ice: 7 × 20 lb + 1 × 10 lb bags, about $45. Warm drinks double the chilling ice.

145 lb of ice

7 × 20 lb + 1 × 10 lb bags · about $45 · 1.5 lb per guest · 250 drinks for 100 guests over 3 h at 80°F

Total, rounded up	145 lb
Chilling the drinks (1:1 ice to drink, drinks start cold)	107.8 lb
Melt over the party	36.6 lb

Coolers that hold it

Ice for 100 people by temperature and party length

Temperature	3 hours	5 hours	8 hours
70°F	137 lb	219 lb	371 lb
80°F	145 lb	237 lb	411 lb
90°F	153 lb	255 lb	452 lb
100°F	171 lb	297 lb	548 lb

Drinks go in	Ice	Bags
Already cold (1:1)	145 lb	7 × 20 lb + 1 × 10 lb
Warm (2:1)	289 lb	14 × 20 lb + 1 × 10 lb

Drinks: 1 per guest plus 0.5 per hour, as 12-oz cans (0.375 qt of drink each).
Chilling ice = drink volume × ratio × 1.15 lb per quart of loose ice. Ratio 1:1 when drinks go in cold, 2:1 when they start warm (the cooler makers' convention).
Melt: we add 50% of the chilling ice for 4 hours at 85°F in shade, scaled by hours and by degrees above freezing; ×1.3 in the sun, ×1.2 above 95°F. This is our estimate, not a lab figure.
Ice in cups: 7 oz per drink, kept in its own cooler so it stays clean.
Bags: the fewest 20 lb and 10 lb bags that cover the total. Coolers: cans that fit at the same ratio from each model's real interior volume.

Loose ice weighs about 1.15 lb per quart (ice is 0.917 g/ml; cubes leave about 40% air). Data as of Oct 2026. Full list of sources: How we calculate.

145 lb for a 3-hour party at 80°F with cold drinks, or 289 lb if the drinks start warm.

7 × 20 lb + 1 × 10 lb bags for 145 lb.

2 × Coleman Classic 120 Marine holds the 250 cans with ice at 1:1.

About 297 lb for 5 hours at 95°F with the cooler in the sun; keep some in reserve and add it halfway.