Units of Measure index

Imperial Measures of Volume


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This page gives Imperial units of volume or cubic measures. Lengths (such as inches, feet, yards and miles) are on the length page and areas or square lengths are on the area page. There is a quick convertor below which gives an answer rounded to 2 decimal places. The metric equivalents on this page are also all to 2 decimal places. There are more advanced conversions on the tables page.

Enter value:   =   ?  

Warning!!! - Imperial measure of volume are not the same as U.S. Customary systems.
Click here for the American system.


Well-known units - pints, gallons, quarts
Smaller units - fluid ounce, gill, cup, fluid drachm, minim, spoons
Dry units - peck, bushel, other units
Beer casks - pin, firkin, kilderkin, barrel, puncheon, tun, hogshead, butt
Cubic measures - cubic inches, feet and yards
Wood measures - cord, cord foot, rick, fathom, Hoppus foot
Other cubic measures or volumes - shipping ton, perch, old Scottish measures

Well-known units - Everyone knew these and used them constantly. Please note that in Britain (unlike America), there are only one set of volume units for both dry and liquid measurement.
conversion
MetricImperial cubicTableInformation
pint568.26 ml34.68 cu inch2 pints = 1 quart
8 pints = 1 gallon
Half pint mark on glass The word 'pint' comes from the French word pinte . It was used in 14C.
Statutory Instrument 1995 No. 1804 allows the use of the pint for dispensing draught beer and cider, and for milk in returnable containers. The regular draft beer measures in Britain are pint and half pint, and in a pub you will be served the beer in a glass with an official stamp on it to show that it is correct measure. There will either be a line on it, or the complete measure is filling the glass to the brim. This explains why there are slop mats on the bar, and beer mats made of card on the tables!
Shell-fish, such as shrimps and prawns, used to be sold in pints or half pints. I remember buying a half pint of prawns measured with a beer glass.
A mnemonic for metric conversion: A litre of water's a pint and three quarters. Or, of course, anything else (it rhymes to help you remember it). This is pretty accurate. A correspondent says "With regard to pint measures and mnemonics, I was always taught that a pint of water weighs a pound and a quarter". Read about fluid ounces to see that is correct. One problem is that you might mix the two mnemonics up!
quart1.14 litres 69.35 cu inch2 pints = 1 quart
4 quarts = 1 gallon
A quart is a quarter of a gallon. There's a saying: You can't get a quart into a pint pot. True!
yard of ale glass A rather silly measure of beer is the yard of ale. This is a special glass which is a yard long. This is a massively long glass, but it's very narrow, so it only contains a quart. It has a rounded end. The idea is to drink the contents in one go. This is hard, not only because of the amount of liquid, but also the shape of the glass means that it is hard to control the flow of liquid to the mouth.
gallon4.55 litres277.42 cu inch8 pints = 1 gallon
4 quarts = 1 gallon
2 gallons = 1 peck
The gallon was mentioned in Piers Plowman (1342), "with a galun of ale"! It comes from the Norman French galon. Petrol in British garages used to be sold in gallons. It's now sold in litres. 5 litres is more than a gallon.
A correspondent writes "As a small boy during holidays in Cornwall in the late 1960s, I remember often being sent to the village shop by my grandmother for 'a gallon of potatoes'. Those were the days..." That certainly is a new one on me! (I thought British potatoes were always sold by the pound, or even by the stone). Another correspondent explains this: "The story given me was that during the war years (WWII), when all the brass weights (along with the church bells) went to become shell cases, the villagers bought their potatoes in the ubiquitous galvanised bucket - which held two gallons of water and weighed about a stone if I remember rightly!  It carried on after the war years because it took time to get the brass back and people had become used to it." Another correspondent says "I assure you 'a gallon of potatoes' was the recognised way to buy them during and well after WW2, well into the 60's, in Cornwall at any rate."
old pewter half pint measure

An old half pint measure

This half pint measure is made from pewter. It is in the People's Palace on Glasgow Green.

An old gallon measure
old gallon measure from Canada
On the left is an old gallon measure from Canada sent by one of my correspondents. While it seems to say George II, it is actually George V, and the 2 refers to London City. This is confirmed by the crest, which has been used by London for centuries.
Canadian bentwood measureCanadian bentwood measure

However, another correspondent said "The measure you have pictured (on the left) wasn't verified in Canada during the reign of George V, as the Canadian system of controlling weights and measures was well established by 1911.  The measure could very well have been found in Canada but would not be legal for trade here unless reinspected and rebranded with Canadian verification sequences." He supplies photos of a Canadian bentwood measure (centre, above) and its verification sequence (right). He has been collecting and researching Canadian Measures for about 25 years now and has a small website here.



Smaller units - less than a pint. These tend to be measures of liquid.
conversion
MetricImperial cubicTableInformation
fluid ounce28.41 ml1.73 cu in20 fluid ounce = 1 pint The abbreviation for the ounce is 'oz', and for fluid ounce, it's 'fl.oz.'
In metric, a millilitre is a cubic centimetre. A fluid ounce is 1.73 cubic inches.
A fluid ounce of water weighs one ounce. There are 20 fluid ounces to a pint and 16 ounces to the pound, which means a pint of water weighs 1¼ lbs. The American system is different, with 16 ounces to the pint.
gill142.07 ml8.67 cu in5 fluid ounce = 1 gill
4 gills = 1 pint
The legal standard English spirit measure is 25ml or 35ml. These are the metric conversions of the old measures of 1/6 gill or 1/4 gill (or 1/5 gill in Scotland).
The gill is sometimes spelled jill. There is an explanation of the nursery rhyme:
          Jack and Jill went up the hill to fetch a pail of water.
          Jack fell down and broke his crown and Jill came tumbling after.

When Charles I scaled down the 'jack' (a two-ounce measure) so as to collect higher sales taxes, the jill, by definition twice the size of the jack, was automatically reduced also and 'came tumbling after.'
cup284.13 ml17.34 cu in10 fluid ounce = 1 cup
2 cups = 1 pint
The British tend to weigh ingredients for cooking rather than measure by volume, but they sometimes measure liquids by volume. However, they used pints and fluid ounces rather than cups. Still, I did find this definition of a British cup. While it agrees with America that a cup is half a pint, the pints are different sizes, so it will be a different measure. Personally, I would say 'half a pint' instead. British recipes never use cups, so if a recipe says 'cup' then it's an American one, and should use an American cup.
fluid drachm
fluid dram
fluidram
3.55 ml0.22 cu in60 minims = 1 fluid drachm
8 fluid drachms = 1 fluid ounce
The drachm is an archaic spelling of dram. A teaspoon was formerly defined as 1 fluid dram.
Dram is also used informally to mean a small amount of liquid, especially Scotch whisky. Obviously this is a different meaning since the Scots drink whisky in glasses bigger than 1/8 fl.oz! Most references assume it means any small glass of whisky, but my father (half-Scots) was sure that it was a specific amount. He thought it was twice a normal English spirit measure. There are some dram glasses on sale on the web which say they are two ounces (presumably fluid ounces) so that would be about right. He also got annoyed at the expression 'wee dram'. A dram is already a small glass of whisky.
However, a correspondent says: "As far as I remember from my Father telling me, and current drinking culture on the East coast of Scotland anyway, a dram was two fingers of spirit in a glass (home measures - heavy drinkers would say index and pinky) and anyone going for a 'wee dram' didn't refer to the volume of liquid but the quantity of drams. i.e just a half dozen or so.I have never heard of anyone going for a big dram, possibly they just forgot by that stage."
minim0.06 ml - 60 minims = 1 fluid drachm This seems to be an apothecaries' measure, which according to Wikipedia is "a system both recent and short-lived"!

Spoons

In British recipes, small amounts of ingredients are often measures in spoons. These seem to be particularly confused. While metric spoons are well-defined, there are older definitions which contradict each other. There are teaspoons (tsp.), dessert spoons for eating pudding and tablespoons (tblsp.) for serving food.
RelationshipTeaspoonDessert spoonTablespoon
Metric2 teaspoons = 1 dessert spoon3 teaspoons = 1 tablespoon5ml10 ml15 ml
Traditional2 teaspoons = 1 dessert spoon4 teaspoons = 1 tablespoon?2 x ?4 x ?
Good Housekeeping's Encyclopaedia (pub. 1973)?3 teaspoons = 1 tablespoon5.97 ml?17.62 ml
Wikipedia1 teaspoon = 1 fluid dram?3.55 ml??

Measuring spoons Actual teaspoons, dessert spoons and tablespoons vary dramatically in size. My cooking suffered accordingly until I bought the standard measures (see right). Also recipes may mention 'level tablespoon' (flat surface), 'rounded tablespoon' (as round above as the spoon is below) and 'heaped tablespoon' (as much as you can get on the spoon). These vary considerably in volume.

It is more worrying that liquid medicine was often prescribed in teaspoons. Now a plastic spoon is usually provided with the medicine, but the dosage in the old days must have varied quite dramatically.



Dry units - such as flour
conversion
MetricImperial cubicTableInformation
peck9.09 litres0.32 cu foot2 gallons = 1 peck
4 pecks = 1 bushel
Official standard measure The peck has been used since the 14C. There's a well-known tongue twister: Peter Piper picked a peck of pickled peppers. You can have a peck of trouble, and you're supposed to eat a peck of dirt before you die, probably no longer true in our fastidious times.
Cities in England used to have official standard weights and measures. Merchants weights and measures would be checked against this to make sure they weren't trying to cheat their customers. This is a standard measure from Manchester dated 1754 and made of cast brass. It is now in the Museum of Science and Industry in Manchester.
bushel36.37 litres1.28 cu foot4 pecks = 1 bushel To hide your light under a bushel means to keep quiet about your abilities. A bushel is a container that holds a bushel of dry goods, and if you up-ended it over a light, then the light would be hidden.
A correspondent says "I have only once had the misfortune to bag oats by the bushel and this would be about 50 years ago. The oats were shovelled from the bulk heap into the bushel measure and then poured into the bag. The bushel measure was a part-barrel - less than half a barrel and possibly about a 1/3 of a barrel. At one time it had been stamped by the Weights and Measures inspectors. The procedure was to fill the bushel to overflowing, and then rap the side once, and once only, to settle the grain, using a bushel stick. This stick was then used to scrape the surplus off the top of the measure leaving a level full, but not over-full, measure. The contents were then teemed into the bag (or sack) and 4 or 5 bushels filled the bag, depending on the size. Great store was given to rapping the bushel properly. Too heavy a rap put too many grains into the bushel, and too light a rap gave poor measure. The traditional bag here was 10 stone or about 5 bushels, but 8 stone (1 cwt) bags were becoming more popular as farm workers got older. The railway bags held 2 cwt and we never filled them with more than 10 stone - we had nobody strong enough to lift them."
Connected with the above, in a Folk Museum, I saw a shop measure with a stick. The stick was supposed to help get the top of the measured material level. However, the stick was straight on one edge and curved on the other. The straight edge would give you good measure. But if the shopkeeper thought that he could cheat you, he would use the curved edge, which would give you short measure!

There were other dry units, such as sack or bag (3 bushels), quarter (8 bushels), chaldron (36 bushels) and load (40 bushels). However, these units would vary according to what they measured, and possibly location. The quarter is supposed to be a quarter of a chaldron, for example, and as you can see, these figures show that it isn't! The chaldron is derived from the word for 'cauldron'. There is a unit of weight called a quarter.

In Newcastle, there were additional volume measures of beatments (a quarter of a peck), kennings (2 pecks) and bolls (2 bushels). Newcastle also seems to have used chaldon as a unit of weight (see Newcastle mining units).

There was a northern dry unit of a windle. This varied, usually about 3 bushels, so was similar to the sack or bag.



Beer casks - Beer is drunk in pints, occasionally quarts, and unwisely gallons. These are larger measures of the casks used to transport and store beer. A barrel is a specific size, so 'cask' is the correct generic term. Dry goods, such as herring, could be packed in casks, and these might be different sizes. A herring barrel was 26 2/3 Imperial gallons. Note that the conversions below are rounded to 2 decimal places.
conversion
MetricImperial cubicGallonsTable
pin20.46 litre0.72 cu foot 4.5 gallons4.5 gallons = 1 pin
firkin40.91 litre1.44 cu foot 9 gallons2 pins = 1 firkin
kilderkin81.83 litre2.89 cu foot 18 gallons2 firkins = 1 kilderkin
barrel163.29 litre5.78 cu foot 36 gallons2 kilderkins = 1 barrel
puncheon327.32 litre11.56 cu foot 72 gallons2 barrels = 1 puncheon
tun981.96 litre34.68 cu foot 216 gallons3 puncheons = 1 tun
hogshead245.49 litre8.67 cu foot 54 gallons6 firkins = 1 hogshead
butt490.98 litre17.34 cu foot 108 gallons2 hogshead = 1 butt
2 butts = 1 ton (or tun)

'Tunne' or 'tunna' (from the French tonneau) was first used for a barrel and then for one of a particular size, and therefore as a measure of capacity and weight - giving us both ton(ne) and tun in English.

This is a cheerful folk song which lists, with great gusto, many of the units of volume.
Here's good luck to the pint pot
Good luck to the Barley Mow
Jolly good luck to the pint pot
Good luck to the Barley Mow
The pint-pot, half-a-pint, gill-pot, half-a-gill quarter-gill, pipkin, and the drum bowl.
Each verse adds something extra, until you get to:
Here's good luck to the barrel
Good luck to the Barley Mow
Jolly good luck to the barrel
Good luck to the Barley Mow
The barrel, the eighteen, the nine, the four-and-half, gallon, half-gallon, quart-pot, pint-pot, half-a-pint, gill-pot, half-a-gill quarter-gill, pipkin, and the drum bowl.
The eighteen, nine and four-and-half are kilderkins, firkins and pins. Some versions are the song may mention these. Some versions replace these with "half barrel", and end with "nipperkin, and the brown bowl" or "round bowl" rather than "pipkin, and the drum bowl". Both nipperkin and pipkins are cups or containers. If the units carry on getting smaller, the last two must be tiny as a quarter-gill is just over a fluid ounce.
You can continue the song with the land-lord, his wife, his daughter (of course!), the drayman, and so on, until you reach the company, who made the beer!

Beer casks used to be made out of wood. The pieces of the sides are called staves.

1200 staves = 1 mille (for a standard cask)

Click here to see how you order beer in Australia.
Click here for American drinks measures.




Well-known cubic units
conversion
Cubic measures and volumes are really the same type of unit, and I have given the cubic conversion of the volume measures above.
A cubic inch is a cube with sides of 1 inch. However 2 cubic inches is not a cube with sides of 2 inches (which would be 8 square inches). It would be a rectangular cube with 1 inch by 1 inch by 2 inch. So it is necessary to learn a different table for cubic units.
MetricTable
cubic inch16.39 cu cm12 x 12 x 12 inches = 1 cubic foot
1728 cubic inches = 1 cubic foot
see inch and square inch
cubic foot479.45 cu cm3 x 3 x 3 feet = 1 cubic yard
27 cubic feet = 1 cubic yard
see foot and square foot
cubic yard0.76 cu metre1760 x 1760 x 1760 yards = 1 cubic mile
5,451,776,000 cubic yards = 1 cubic mile
see yard and square yard



Wood measures
conversion
MetricTableInformation
cord3.62 cu metres128 cubic feet = 1 cord
4 x 4 x 8 feet = 1 cord
16 x 4 x 2 feet = 1 cord
I thought the cord was an American unit, but a corresepondent corrected me. He said that it was used in Northumberland. "My father was using cords in his younger days when he worked in a timber yard. I remember him showing me a strange tape measure, marked with units about 4" apart, that they used to work out the cordage of a piece of timber from its length."
Also, a webpage on the Common Rights in the New Forest mentions that a cord is a stack of wood in 4 foot lengths, 4 feet high and 8 feet long. It is concerned with Right of Fuelwood (Estovers).
In some districts the cord had dimensions of 16 feet by 4 feet by 2 feet. This is still 128 cubic feet.
cord foot0.45 cu metres16 cubic feet = 1 cord foot
8 cord feet = 1 cord
measured ricks1.21 cu metres3 measured ricks = 1 cord A correspondent says "A rick (unmeasured) is a any size stack of cornstalks, wood, straw or similar stuff, left in the field. Any old pile of firewood may also be called a rick, although most people just call it a woodpile. It takes about 8 cords of wood to heat a home for the entire winter."
(cubic) fathom6.12 cu metres216 cubic feet = 1 (cubic) fathom
6 x 6 x 6 feet = 1 (cubic) fathom
This website claims that in England, a fathom is a measure of capacity for round wood = 216 cubic feet, that is, the volume that would be occupied by a stack 6 feet long, 6 feet wide, and 6 feet high. This would be a cubic fathom. It quotes "Fathom of wood is a parcel of Wood set out, six whereof make a Charcoal-Fire." They seem to like the number six! The same website also claims that in Yorkshire, England, the fandam (an alternative spelling) was a measure of the circumference of haystacks, measured by a circle of people hugging the stack, their outstretched hands just touching. This would be because the word is derived from 'embrace'. The distance from one finger-tip to another is about a fathom.
Hoppus foot36047.35 cu cm1.273 cubic foot = 1 Hoppus foot
0.785 Hoppus foot = 1 cubic foot
The Hoppus foot is used for round or rough-squared timber and the formula uses the mid-quarter-girth (M.Q.G.) in inches, squared, then multiplied by the length in feet and then divided by 144 to give H.ft. The girth is measured in inches at the mid-point between the butt and the tip and then divided by 4 to get the M.Q.G. Quarter Girth tapes are available, with 66' tapes for the length, and ready-reckoner tables for standard types of timber eg. pit props. Other common timber terms were the ton for firewood and pulpwood, the bundle for stakes and pea-sticks etc., and the linear foot for pit-props and fence rails etc. Wood for chipboard or fibreboard is sometimes traded in units of 100 cu. ft. of piled chips, equivalent to 50 H.ft. of solid wood.



Other cubic units
conversion

The Observer newspaper had a lot of trouble with the definition of a ship's tonnage. It appears in their readers' corrections column 3 weeks running. So for everyone else, here is their final definition:
Tonnage is a measure of the internal volume of a ship, devised as a basis for charging harbour dues. It is said to originate with 'tuns' of wine, one tun being equal to 252 gallons, roughly 42 cubic feet. The modern tonnage measurement, introduced by the Merchant Shipping Act 1854, is 100 cubic feet. Gross tonnage is the internal volume of the ship and Net (or Register) is the Gross tonnage less non-earning spaces, such as engine room and crew accommodation.
However, I've received the following correction "Tonnage of ships is a difficult subject, and now the Gross Ton (GT) actually can't be converted. It is now a formula, adopted in 1969 and applicable to all ships since 1994:
1 GT= (0.2+0.02*logV)*V
where V is the volume measured in cubic metres of enclosed spaces on the ship. (The logarithm is base 10.)"
In fact, there is another ton which measures volume. This is the largest beer cask, called a ton or tun. But this is 34.6 cubic feet.

I have seen a reference to 1 perch of stone being 24 cubic feet. This is very strange. A perch is a length, the same as a rod or pole, and five and a half yards long. They are used in land measurement. They are sometimes used as square units, that is a (square) rod = a rod times a rod. The word 'square' is left out. But a (cubic) perch would be 4492.125 cubic feet! So I don't know if this unit is connected at all.




Old Scottish measures
4 gills = 1 mutchkinA Scottish gill was about 3/4 Imperial gills.
A Scottish pint was about 2 Imperial pints 4 gill.
This was because in Scotland, there were 16 gills to the pint rather than 4.
2 mutchkins = 1 chopin
2 chopin = 1 pint
8 pints = 1 gallon



A frivolity from the splendid online comic xkcd:

xkcd comic




A final frivolous comment: In 2012, petrol is sold in litres (in Britain) and distances sometimes quoted in kilometres, yet the efficiency of cars is quoted in miles per gallon! In fact, the mile, yard, foot or inch are still the legal measurements for road traffic signs, distance and speed measurement. Speed limits are given in miles per hour, for example. But it's even more complicated than that. The metric fuel efficiency measure is litres per 100 kilometres, which is not only a ratio of different units, but the ratio is the other way up! (That is, Imperial has length divided by distance, and metric has distance divided by length.)