Drinks and ice calculator
Juice boxes, water, grown-up drinks and bags of ice. Enter your guests and how long the party lasts.
Festidy's plan counts drinks and ice from your RSVPs and the length of your party.
Make my party planHow we calculate
- Kids' drinks: the flavored ones (juice boxes, pouches, lemonade, sports drinks), 1 per kid an hour. A 2-hour party is 2 per kid.
- Grown-ups' drinks: 2 in the first hour, then 1 an hour (soda, sparkling water, beer or wine). A 3-hour party is 4 each.
- Water: counted on its own, 8 oz per kid an hour and 4 oz per grown-up an hour. We show it as small (8 oz) bottles and as gallons, rounded up to the half gallon (a gallon is 16 cups). On a hot day we add half again.
- Ice: about 2 lb per guest, doubled on a hot day (85°F or more) or outdoors in the heat. An ice maker's party guide says one to two pounds a person, and more outdoors in warm weather.
- Bags: we assume 7 lb and 20 lb bags and round up. Stores sell other sizes, so check the bag and divide.
- Kids' party length: 2 hours is the sweet spot for most ages, and 90 minutes for ages 1 to 3.
Last updated October 21, 2026. Free, no sign-up.
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Tips for coolers and ice
- Keep one bag just for drinks. Use sealed ice for cups. Use the rest to chill cans and bottles.
- Use two coolers. One for drinks that get opened all afternoon, one for food that should stay shut.
- Chill the drinks first. Cans from the fridge melt far less ice than cans from the garage.
- Ice on the bottom, drinks, then ice on top. Fill the gaps, keep the lid closed and keep the cooler in the shade.
- Hold back a bag or two. Keep them in the freezer and top up halfway through the party.
Questions
How much ice for 50 people?
About 100 lb, which is 15 bags of 7 lb or 5 bags of 20 lb. On a hot day or outdoors in the heat, double it to 200 lb: 29 bags of 7 lb or 10 bags of 20 lb.
How many juice boxes for a kids' party?
One per kid for every hour. For 12 kids at a 2-hour party that is 24 juice boxes, and for 20 kids it is 40. Water is counted on top.
How many drinks per person for a party?
Kids get 1 flavored drink an hour. Grown-ups get 2 in the first hour and 1 an hour after, so 4 each at a 3-hour party. Add water for everyone.
How many bags of ice for 20 people?
40 lb, which is 6 bags of 7 lb or 2 bags of 20 lb. On a hot day it is 80 lb, or 12 bags of 7 lb or 4 bags of 20 lb.
How much water per person for a party?
8 oz per kid an hour and 4 oz per grown-up an hour. For 12 kids and 8 grown-ups over 2 hours that is 32 small bottles, or 2 gallons in a dispenser. Add half again if it is hot.
How much ice for a party on a hot day?
Double it: about 4 lb a guest instead of 2. For 25 guests that is 100 lb, or 15 bags of 7 lb.