Keg and beer calculator
Enter the adults who drink beer and how many each will have to see how many kegs — or cases — to order. A full-size half barrel holds 15.5 gallons: about 165 twelve-ounce beers.
Enter your measurements
More options: Beer drinkers · Per hour · Foam
- Or kegs of the size picked above
- 2 kegs · half barrel
- Beers to pour
- 200 beers
- Beers per keg at this pour (before foam)
- 165
- Or cases of 24 cans (12 oz, no foam loss)
- 9 cases
- Spare beer in the kegs of the size picked
- 50%
- Beer needed (incl. foam)
- 20.6 gal
100 adults × 50% = 50 beer drinkers × 4 beers (1 + 1 × 3 more hours) = 200 beers
200 beers × 12 oz × 1.1 foam = 20.6 gal ÷ 15.5 gal per keg = 2 kegs · best fit with 10% spare: 1 half barrel + 1 quarter barrel (248 twelve-ounce pours)
- A keg needs to stay cold — in a tub of ice or a kegerator — and a party pump needs a few minutes to settle after the keg is moved. Ask the store which coupler (tap) the keg needs.
- Two half barrels is a lot of beer if it is not all drunk; a half barrel plus a quarter, or several sixths of different beers, may suit the crowd better. Ask about returning untapped kegs.
Quick answers for common sizes
| Example | Answer |
|---|---|
| How many beers in a keg | about 165 twelve-ounce beers (124 pints) |
| How many kegs for 100 guests | a half barrel, plus a sixth barrel or cans to spare |
Beers per keg and kegs needed, by keg size (guests as above)
| Keg | Beers per keg at this pour (before foam) | Or kegs of the size picked above |
|---|---|---|
| half barrel | 165 | 2 kegs |
| quarter barrel | 83 | 3 kegs |
| sixth barrel | 55 | 4 kegs |
| mini keg | 14 | 16 kegs |
Keg sizes come from the barrel: by federal definition a barrel of beer is 31 US gallons, so a “half barrel” — the standard full-size keg — is 15.5 gallons. KegWorks, which sells draft equipment, lists the common sizes with the number of beers each pours.
Keg size chart
| Keg | Gallons | 12 oz beers | 16 oz pints | Same as (24-can cases) |
|---|---|---|---|---|
| Half barrel | 15.5 | about 165 | about 124 | about 6.9 |
| Quarter barrel (pony) | 7.75 | about 82 | about 62 | about 3.4 |
| Sixth barrel | 5.16 | about 55 | about 41 | about 2.3 |
| Cornelius | 5 | about 53 | about 40 | about 2.2 |
| Mini keg (5 L) | 1.32 | about 14 | about 10 | about 0.6 |
How many kegs
beers = adult guests × share who drink beer × beers each kegs = beers × pour size × (1 + foam) ÷ keg size
Those pour counts assume every glass is poured clean. A party pump on a keg that was just carried in pours foam until it settles, so the calculator adds 10% by default. A 12 oz pour is NIAAA’s standard drink of regular beer; a 16 oz pint is one and a third.
Worked examples
- How many beers in a keg — half barrel, quarter and sixth, in cans and pints.
- How many kegs for 100 guests — a wedding or reunion, and when cans are easier.
Keg or cans?
- Kegs suit one or two beers for a crowd and keep cans out of the trash. They need ice or a kegerator, a tap, and someone who can change a keg.
- Cans suit variety, small groups and parties that move around; they chill in a tub of ice and leftovers keep.
- Deposits: keg rentals usually carry a deposit on the keg and the tap.
What you’ll need
- Party keg pump (tap)Budget price
A hand-pumped tap for a rented keg. Most US domestic kegs use a D-system coupler; ask the store which one yours needs.
See options on Amazon (opens in a new tab) - Large coolerPremium price
A big cooler for drinks and ice. A drain plug matters when you are melting 40 lb of ice over an afternoon.
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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As an Amazon Associate we earn from qualifying purchases. Links to products are affiliate links — they cost you nothing extra and help keep these calculators free.
Frequently asked questions
How many beers are in a keg?
A full-size half-barrel keg holds 15.5 gallons: about 165 twelve-ounce beers or about 124 pints (KegWorks). A quarter barrel holds about 82 twelve-ounce beers, a sixth barrel about 55.
How many cases of beer is a keg?
A half barrel is about the same as 6.9 cases of 24 twelve-ounce cans; a quarter barrel about 3.4 cases; a sixth barrel about 2.3.
How many kegs for a wedding of 150?
If half of 150 adults drink beer, three each, that is 225 beers — about 2,970 oz with 10% for foam, or two half barrels.
What is a pony keg?
A quarter barrel: 7.75 gallons, about 82 twelve-ounce beers by KegWorks’ chart.
Related guides
Sources
- KegWorks — Guide to beer keg sizes (opens in a new tab) — Half barrel 15.5 gal (about 165 twelve-ounce pours, 124 pints); quarter 7.75 gal (82 / 62); sixth 5.16 gal (55 / 41); Cornelius 5 gal; 5 L mini keg 1.32 gal (about 14 twelve-ounce pours).
- eCFR 27 CFR 25.11 — Definitions: barrel (Cornell LII copy) (opens in a new tab) — A barrel of beer, as a unit of measure, is 31 U.S. gallons.
- NIAAA — What is a standard drink? (opens in a new tab) — One standard drink holds 0.6 fl oz (14 g) of pure alcohol: 12 fl oz of regular beer (about 5%), 5 fl oz of table wine (about 12%), or 1.5 fl oz of distilled spirits (about 40%).
- USDA/HHS — Dietary Guidelines for Americans, 2025–2030 (opens in a new tab) — “Limit Alcoholic Beverages”: consume less alcohol for better overall health; pregnant women, people recovering from alcohol use disorder or unable to control how much they drink, and people on interacting medications should avoid alcohol completely. No daily drink numbers are given.
- CDC — Moderate alcohol use (page dated January 14, 2025) (opens in a new tab) — Defines moderate drinking for adults of legal drinking age as two drinks or less in a day for men and one drink or less for women, citing the 2020–2025 Dietary Guidelines.