How many pints are in a standard US half-barrel keg?

A US half-barrel keg holds 58.67 litres (15.5 US gallons). At a UK pint (568 ml) that yields 103 full pints; at a US pint (473 ml) it yields 124 full pints. The calculator shows the exact figure for any pour size.

What is the difference between a US pint and a UK pint?

A US liquid pint is 473 ml (16 US fl oz), while a UK imperial pint is 568 ml (20 UK fl oz) — about 20% larger. The difference adds up across a full keg, so always specify which pint you mean when ordering or pricing.

How many litres is a firkin?

A UK firkin equals 9 imperial gallons, which is 40.91 litres. It is the most common cask size in British real-ale pubs and yields around 72 UK pints.

What is a sixtel keg?

A sixtel (also called a sixth barrel) holds one-sixth of a US beer barrel, which is 19.55 litres or 5.16 US gallons. It is popular for craft beer bars because it fits in a standard under-counter fridge and yields roughly 55 US pints.

How is keg waste calculated?

Waste is the liquid left after the last complete pour: total volume (ml) modulo pour size (ml), converted back to litres. Example: a 50 L euro keg with 473 ml US-pint pours gives 105 full pints and 35 ml left over — less than 0.1 % waste.

What is a Cornelius (corny) keg?

A Cornelius keg is a 5 US gallon (18.93 L) stainless-steel pressure vessel originally used by soft-drink companies and adopted by home brewers. It uses ball-lock or pin-lock disconnects and gives about 40 UK pints or 40 US pints from a single fill.

Keg Size Calculator — Gera Tools

Whether you are planning a party, running a bar, ordering for a wedding or simply trying to work out how many bottles your homebrew will fill, this keg size calculator converts any keg volume instantly and tells you exactly how many servings you will get — down to the last millilitre.

Standard keg sizes explained

The world has no single standard for kegs. Three separate systems are in everyday use, and confusing them is a common (and expensive) ordering mistake.

US barrel system — American craft beer is sold in fractions of the US beer barrel (31 US gallons / 117.35 L). The sizes you will encounter most often are:

Name	Litres	US gallons
Half barrel (full keg)	58.67	15.5
Quarter barrel (pony)	29.34	7.75
Sixth barrel (sixtel)	19.55	5.16
Cornelius keg	18.93	5.00

UK cask system — British real-ale uses imperial gallons. The firkin (9 gal / 40.91 L) is the standard pub cask; the pin (4.5 gal / 20.46 L) suits smaller venues and festivals; the kilderkin (18 gal / 81.83 L) is used for very busy outlets.

European DIN system — Continental lager kegs follow the DIN 6647 standard in 20 L, 30 L and 50 L variants. The 50 L keg is the single most common size in European bars and is what most draught lager systems are designed around.

How it works

The calculator performs two operations for every input.

Unit conversion. One litre is defined as exactly 0.001 m³. All other units derive from this:

1 US gallon = 3.785 41 L → 1 L = 0.264 172 US gal
1 UK (imperial) gallon = 4.546 09 L → 1 L = 0.219 969 UK gal
1 US fl oz = 1/128 US gal → 1 L = 33.814 US fl oz
1 UK fl oz = 1/160 UK gal → 1 L = 35.195 UK fl oz
US pints = US gallons × 8; UK pints = UK gallons × 8

Servings. Given a keg of V litres and a pour of P ml:

exact servings = (V × 1 000) ÷ P

full servings = floor(exact servings)

leftover = (V × 1 000) mod P, in ml

The remainder is what stays in the keg after the last complete pour — typically a few millilitres, negligible in practice but useful to know for event budgeting.

Worked example

A venue orders a 50 L euro keg and serves UK pints (568 ml):

Exact servings: (50 × 1 000) ÷ 568 = 88.03
Full UK pints: floor(88.03) = 88 pints
Leftover: (50 000 ml mod 568 ml) = 50 000 − (88 × 568) = 50 000 − 49 984 = 16 ml

At a US pint (473 ml) the same keg yields 105 full pints with just 335 ml waste. The 20% size difference between a US and UK pint accounts for an extra 17 pints from the identical keg — worth knowing when comparing transatlantic bar costs.

Formula note

US barrel conversions use the legal US beer barrel: 1 US beer bbl = 31 US gal = 117.347 7 L (not the petroleum barrel of 42 gal). UK cask sizes are exact integer multiples of the imperial gallon (4.546 09 L), which is why UK measures sometimes look uneven in litres but are tidy in gallons.