Liters to Pints

A Litre of Beer Measured Against the British Pint

A brewery lists its taproom keg as 30 litres, a delivery note says 50 L, and the glass waiting on the bar is stamped PINT. Somewhere between the cellar and the till, someone has to know how many servings that metric figure actually pours, because in Britain the pint is not a rough serving size — it is a quantity fixed in law and checked by trading standards.

The gap matters at both ends of the cellar. Get it wrong when ordering and a busy Saturday runs dry two kegs early; get it wrong at the tap and every glass is either short measure or free beer.

Conversion factor: 1 imperial pint = 568.26125 mL, so 1 L = 1.7598 imperial pints. A 30 L keg holds 52.8 pints before any line or sediment loss. Note that this page opens on pt, the smaller US pint of 473.176473 mL — switch the right-hand list to imp pt when you mean a British one.

Where Litres and Pints Meet Over a Bar

The serve the law fixes

Draught beer and cider in the UK may only be sold as a third of a pint, a half, two-thirds, or multiples of a half. The glass itself has to be a certified measure.

The cellar stock behind it

Kegs arrive in round metric sizes — 20, 30 and 50 L are the usual ones — while the yield that matters to a tenant is counted in pints sold.

Bottles labelled in millilitres

Packaged beer comes as 330, 440 or 500 mL. Only a 568 mL bottle carries a full pint, which is why a half-litre import feels short beside a draught glass.

Flights and small measures

Thirds and two-thirds turned a tasting flight into something a pub can lawfully sell. Three thirds add up to exactly one pint, which keeps the price list tidy.

Reading a Metric Beer Volume in Pub Measures

The pair on this page starts as litres on the left and pints on the right. Before you trust the answer, make sure the right-hand list is showing the pint you actually mean.

Put the keg or bottle volume in on the left

Type the litre figure exactly as the delivery note prints it. A comma stands in for a dot if that is how your keyboard runs, and stray spaces are dropped, so 1,5 and 30 000 both read correctly.

Choose imp pt, not pt

Open the searchable list on the right and type "imp" to bring up the imperial pint. The plain pt entry is the American one and will overstate your serving count by about a fifth.

Turn it round when the spec is in pints

Either type straight into the right-hand box — both fields accept input and the other one follows — or press the swap arrows (↔) to flip the whole pair when a price list is written pints first.

Lift the plain figure for a stock sheet

Each field has a copy button that hands over the digits alone, with no unit and no thousands spacing, which is what a cellar spreadsheet wants. Ctrl + C inside the field behaves the same way.

Keg yield is not keg volume. The arithmetic gives a theoretical pint count; line cleaning, the first pull of the day, sediment and spillage all come off it. Cellars normally budget a few percent of every container as unsellable.

UK Legal Draught Measures and the Glasses They Fill

Weights and measures rules allow draught beer and cider to be sold only in the quantities at the top of this table: a third of a pint, a half, two-thirds, or any multiple of a half pint. Two-thirds joined the list in 2011, which is why schooner glasses appeared in British pubs relatively recently. The last three rows are volumes you will meet at a bar that are not permitted draught quantities.

Measure at the bar	Millilitres	Litres	Where it turns up
Third of a pint	189.42 mL	0.1894 L	Tasting flights and very strong beers
Half pint	284.13 mL	0.2841 L	The long-standing smaller serve
Two-thirds (schooner)	378.84 mL	0.3788 L	Permitted since 2011, common for craft keg
One pint	568.26 mL	0.5683 L	The default draught serve
Pint and a half	852.39 mL	0.8524 L	Allowed as a multiple of a half pint
Two pints	1136.52 mL	1.1365 L	Usually poured as two glasses or a jug
Half-litre bottle	500 mL	0.5 L	0.88 pint — 68 mL under a full one
One litre from a stein	1000 mL	1 L	1.76 pints, a festival serve rather than a draught quantity
American pint glass	473.18 mL	0.4732 L	0.83 of a British pint, shown here for contrast

Glassware then comes in two styles. A brim measure holds exactly one pint filled to the very top, so any foam eats into the beer. A lined glass is oversized with a pint mark below the rim, leaving room for a head above the line — which is why bars pouring cask ale with a thick collar tend to prefer them.

Details That Help When Comparing Beer Volumes

Both pints sit in the same dropdown

Typing a few letters into either unit list filters it, so moving between the imperial pint and the US one takes a keystroke rather than a fresh page.

Results appear as you type

There is nothing to press. Work down a delivery note keg by keg, overwriting the left-hand figure, and the serving count keeps pace with every edit.

Fine enough for a third of a pint

Answers carry up to eight decimals, so a small measure such as 0.1894 L stays exact instead of collapsing to a rounded 0.19.

Numbers ready for the stock book

The per-field copy button strips the unit and the digit spacing, so what lands in a spreadsheet cell is a clean number it can add up.

Questions About Pints, Glasses and Legal Measures

Why does a British pint hold more beer than an American one?

The two countries kept different fluid ounces and then counted different numbers of them into a pint. Britain's imperial pint is 20 imperial fluid ounces, 568.26125 mL, built on a gallon defined as the volume of ten pounds of water. The American liquid pint is 16 US fluid ounces, 473.176473 mL, descended from an older English wine gallon. That leaves the British pint 20.1% larger, so a visiting drinker ordering "a pint" gets noticeably more on one side of the Atlantic than the other.

What is the crown or CE mark stamped on a pub glass?

It certifies the glass as an approved measuring instrument rather than mere decoration. For most of the twentieth century British glasses carried a crown stamp with a verification number; from 2006 newly made glasses moved to a CE mark under European measuring-instrument rules, while crown-stamped glasses already in service stayed lawful. Britain now uses its own UKCA marking, and since 2022 the crown may be added back alongside it as an optional decorative symbol. Whichever mark it carries, the glass has been checked to hold its stated quantity within tolerance, and that is what makes serving a pint in it legal.

Does the foam on top count as part of my pint?

You are entitled to a full pint of liquid. In practice the head is treated as part of the drink, and long-standing industry guidance accepted by trading standards is that a served pint should be at least 95% liquid — roughly 540 mL out of the 568 mL. Ask for a top-up if the glass looks short and the bar should oblige. An oversized lined glass avoids the argument altogether, since the pint mark sits below the rim with the head above it.

Why do bars now offer two-thirds and third measures?

Until 2011 the only lawful draught quantities were a third, a half and multiples of a half, which left an awkward jump from 284 mL straight to 568 mL. Adding two-thirds gave 378.84 mL — a sensible glass for a beer at 7% or 8% where a pint is too much and a half feels mean. Thirds do the same job for tasting flights: three of them make exactly one pint, so a flight of three prices neatly against a single serve.

Is a 500 mL bottle basically a pint?

No, it falls 68.26 mL short — about 12% less beer, or roughly two mouthfuls. Half a litre is the standard bottle and can size across most of Europe, so imported beer arrives in it and British brewers have largely followed. A true pint bottle is labelled 568 mL and is now mostly reserved for traditional ales. When comparing price per serve, convert both to the same unit first, or the bottle will look better value than it really is.