How much coffee for a group?
Whether you are serving coffee at a meeting, a church breakfast or a wedding, the calculation has three steps: how much brewed coffee people will drink, how much ground coffee that takes, and how many brewing batches your equipment allows.
The formulas
- Brewed coffee = people × cups per person × cup size
- Ground coffee = brewed volume (liters) × strength (grams per liter)
- Water to add = brewed volume + about 2 × the coffee’s weight, because spent grounds hold roughly twice their weight in water
The Specialty Coffee Association’s “golden cup” ratio is about 55 to 60 g of coffee per liter of water (roughly 1:17). Catering urns often run a little weaker, around 50 g per liter.
Example
60 people drinking 1.5 cups of 8 fl oz each drink 720 fl oz, or 5.6 gallons (21.3 L) of coffee. At 60 g per liter that is 1,277 g, or 2.8 lb of ground coffee: four 12 oz bags. With a 3-gallon urn, you will brew 2 batches, and you should pour in about 6.3 gallons of water.
| People | Cups (8 oz, 1.5 each) | Ground coffee at 60 g/L |
|---|---|---|
| 20 | 30 | 0.9 lb |
| 50 | 75 | 2.3 lb |
| 100 | 150 | 4.7 lb |
| 200 | 300 | 9.4 lb |
How many cups per person?
- Morning meetings: about 1.5 to 2 cups per person.
- After a dinner: about 1 cup per person, with fewer takers.
- All-day events: plan 3 or more, and decaf for about a quarter of guests.
Brewing tips
- Use a medium-coarse grind for urns and large drip brewers.
- Coffee keeps its flavor for about 30 to 60 minutes on a warmer; an insulated carafe keeps it longer without scorching.
- Note that the “cups” marked on urns are often 5 oz, not 8 oz: a “100-cup” urn holds about 4 gallons.
- Offer milk at about 1 to 2 oz per cup, and sugar packets at 1 to 2 per person.