COLD BREWCoffee Concentrate for a Crowd
The quick answer
Scale the 1:4 cold brew ratio to feed a crowd: use 250g (about 2.5 cups) coarsely ground coffee to 1,000g (4 cups) cold water. Steep 18-24 hours, strain, and refrigerate. Each 2oz serving of concentrate makes one 12oz drink diluted 1:1, giving you 12-16 servings per batch.
Hosting brunch for 15 people and want iced coffee without standing at a machine all morning? One big-batch cold brew concentrate brewed the night before handles it all.
Scaling cold brew is one of the easiest things in home coffee-making. The 1:4 ratio stays fixed regardless of batch size. Double the recipe for 20+ servings; triple it for a large event. The only constraint is container size - you need something large enough to hold the water and grounds with room to stir.
A large glass pitcher, a clean stockpot, or a 1-gallon jar all work as brewing vessels. Avoid reactive materials like unsealed cast iron or thin aluminum. Stainless steel, glass, and food-grade plastic are all fine. For very large batches, a painter's straining bag or cheesecloth draped in a colander is the most practical filtering method.
Steeping temperature is unchanged for large batches. Refrigerate for 18-24 hours just as you would a small batch. The only difference: a large container takes longer to reach temperature in the fridge, so start brewing 2-4 hours earlier to account for the initial chill-down time.
Presentation is worth thinking about for a crowd. Pour concentrate into a glass pitcher labeled 'cold brew concentrate.' Set out a separate pitcher of water and one of milk. Let guests dilute to their preference. This setup means people control their own strength, which is a small but appreciated detail at any gathering.
Dial it in before you make it
Get the coffee-to-water ratio right for concentrate or ready-to-drink.
| Ingredient | Amount |
|---|---|
| Coffee grounds | 189.6 g |
| Coffee grounds (tablespoons) | 35.8 tbsp |
| Water | 948 g |
| Water (cups) | 4.00 cups |
Serving tip
Dilute 1:1 with water or milk to serve — this batch makes ~8.0 cups of ready-to-drink cold brew.
1 tbsp ground coffee ≈ 5.3 g · 1 cup water = 237 g · 1 fl oz water = 29.57 g. Steep 12–24 h in the refrigerator.
Make it
Makes 12 -16 drinks
Ingredients
Steps
We have used this big-batch method for brunch parties of 8-20 people. A single 64oz batch (250g coffee, 1000g water) produces enough concentrate for 16 drinks and requires about 10 minutes of active effort. The convenience-to-effort ratio is one of the best in home coffee-making.
Pro tips
- Brew the night before the event - 18-22 hours fits any morning schedule and gives consistent results.
- Double-filter for a crowd: run through cheesecloth first, then a paper filter to remove fine particles.
- Make a simple label listing the dilution ratio (1:1 with water or milk) so guests know how to serve themselves.
- Store concentrate in multiple smaller jars rather than one large container for easier pouring throughout the event.
- The concentrate keeps for 2 weeks refrigerated, so you can brew up to two weeks ahead of the event.
Made this? How did it go?
Frequently asked questions
How much cold brew concentrate do I need per person?
Plan for 2oz (60ml) of concentrate per serving, diluted 1:1 with water or milk and poured over ice in a 12-16oz glass. For 12 people, brew at least 24oz (710ml) of strained concentrate.
What container is best for brewing a large batch of cold brew?
A 1-gallon glass jar, a large glass pitcher, or a clean food-grade stockpot all work well. Avoid unsealed reactive metals. Glass is the easiest to clean and does not retain flavors between batches.
Can I make cold brew concentrate more than 24 hours ahead?
Yes. Strained concentrate keeps in the fridge for up to 2 weeks. Brew it a week in advance if needed, as long as it is stored sealed and refrigerated. Never leave unfiltered grounds in the brew past 24 hours.
How do I filter a large batch of cold brew?
Use a large fine-mesh strainer lined with cheesecloth or a coffee filter, set over a large bowl or pot. Pour slowly in batches. For the clearest result, run the filtered brew through a paper filter a second time.
Should I serve cold brew concentrate at a party straight or already diluted?
Set out concentrate alongside pitchers of cold water and milk so guests can dilute to taste. Most prefer 1:1 (concentrate to water), but some like it stronger or weaker. Letting them choose always goes over well.
Written by
Jack Shi
Jack Shi is an independent developer and the founder of CLOOMS, where he builds focused tools and web utilities — including Home Cafe Lab. He tests every recipe and guide in a real home kitchen, and his guiding principle is simple: find a real, specific need and solve it as plainly as possible.
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