Coffee calculator: how much coffee for a crowd or an urn
Enter your guests and cups each, or the cups your urn makes, to see how much ground coffee to use. An urn “cup” is 5 fl oz, and a 100-cup urn takes about 6½ to 7 cups of grounds by Hamilton Beach’s chart.
Enter your measurements
- In measuring cups of grounds (approx.)
- 8.1 cups
- Urn “cups” of water (5 oz each)
- 120 cups
- Water
- 4.7 gal
- Urn size
- 2 × 100-cup urns, or brew in rounds
- Brewing time (approx.)
- about 120 minutes (about 1 minute per cup), plus warming
50 drinkers × 1.5 × 8 oz = 4.7 gal = 120 cups at 5 oz
Hamilton Beach chart, 120 cups: 21 oz of grounds (≈ 8.1 cups)
- Fill the urn with water to the cup line first, then add the grounds to the basket. Do not fill past the top line.
- Hot coffee and kids do not mix: keep the urn at the back of the table, with the cord out of reach.
Quick answers for common sizes
| Example | Answer |
|---|---|
| How much coffee for a 100 cup urn | 6½–7 cups of grounds (about 1.1 lb) |
Coffee by number of drinkers (cups each and size as above)
| Coffee drinkers | Ground coffee | Urn “cups” of water (5 oz each) | Water |
|---|---|---|---|
| 10 | 5.3 oz | 24 cups | 0.9 gal |
| 25 | 11 oz | 60 cups | 2.3 gal |
| 50 | 21 oz | 120 cups | 4.7 gal |
| 75 | 31.5 oz | 180 cups | 7 gal |
| 100 | 42 oz | 240 cups | 9.4 gal |
| 150 | 63 oz | 360 cups | 14.1 gal |
The most confusing number in crowd coffee is the “cup”. Coffee urns and coffee makers count in 5 fl oz cups — Hamilton Beach’s manual says so in so many words — so a “100-cup” urn holds 500 oz of coffee, about 62 eight-ounce mugs. Plan by what your guests actually drink from, then convert.
How much coffee for an urn
| Water level (5 oz cups) | Ground coffee | Grams | Fills about (8 oz mugs) |
|---|---|---|---|
| 20 cups | 1½–2 cups | 110–147 g | 12 |
| 40 cups | 3–3½ cups | 221–257 g | 25 |
| 60 cups | 4–4½ cups | 294–331 g | 37 |
| 80 cups | 5¼–5¾ cups | 386–423 g | 50 |
| 100 cups | 6½–7 cups | 478–515 g | 62 |
For drip machines and pour-over, the Specialty Coffee Association’s brewing ratio is about 55 g of coffee per litre of water. University of Missouri Extension’s rule of thumb, 1 lb of coffee for 40 to 50 servings, lands in the same place.
water = drinkers × cups each × cup size urn cups = water ÷ 5 fl oz urn grounds: from the Hamilton Beach chart · drip grounds = litres × 55 g
Worked example
How much coffee for a 100 cup urn — with what “100 cups” really serves.
Tips
- Start early. Hamilton Beach’s 45-cup urn manual allows about a minute per cup to brew; a big urn takes well over an hour from cold.
- Coarse grind for percolators. Fine grounds slip through the basket into the coffee.
- Two urns, or one and a drip machine. One for regular, one for decaf, labelled.
- Extras: cream, sugar, stirrers and cups — Clay County’s quantity table plans 1 to 1½ quarts of cream for 50.
What you’ll need
- Coffee urn (100 cup)Mid-range price
Brews and holds coffee for a crowd. Check how many cups it actually makes and how long it takes to brew before guests arrive.
See options on Amazon (opens in a new tab) - Digital kitchen scaleBudget price
Weighs cooked meat, cheese and batter so portions match the plan instead of guesswork.
See options on Amazon (opens in a new tab) - Plastic party cups (16 oz)Budget price
Guests lose track of their cup, so plan two or three per person. A marker by the stack helps.
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Frequently asked questions
How much coffee for 100 people?
At one 8 oz cup each, 100 people drink about 800 oz — 160 urn cups. That is about 790 g (1¾ lb) of ground coffee by the Hamilton Beach chart’s rate, in two 100-cup urns or one urn brewed twice.
How many cups of coffee in a pound?
University of Missouri Extension says 1 lb of coffee makes about 40 to 50 servings. Hamilton Beach’s urn chart uses a little over a pound for 100 five-ounce cups.
What is a cup on a coffee urn?
Five fluid ounces (150 ml), per Hamilton Beach’s manual. A 30-cup urn holds 150 oz — about nineteen 8 oz mugs.
How long does a coffee urn take to brew?
About a minute per cup, by Hamilton Beach’s 45-cup urn manual — about 45 minutes for a full 45-cup urn, and longer for bigger ones. Start it before guests arrive.
Sources
- Hamilton Beach — Commercial coffee urn (40, 60 and 100 cup) use and care manual (opens in a new tab) — 1 cup = 5 oz (150 ml). Ground coffee by water level: 20 cups 1½–2 cups (110–147 g) … 100 cups 6½–7 cups (478–515 g). Percolates within 8 minutes.
- Hamilton Beach — 45 cup coffee urn manual (opens in a new tab) — Brew at least 15 cups; allow about one minute per cup of brewing time.
- Specialty Coffee Association — Understanding coffee sweetness (opens in a new tab) — Brewing at a ratio of 55 g of coffee per litre.
- University of Missouri Extension — In a Pinch: Food Yields (MP563) (opens in a new tab) — 1 lb of coffee makes about 40 to 50 servings.
- Clay County, Minnesota — Amounts of food to serve fifty (opens in a new tab) — Coffee cream: 1 to 1½ qt for 50.