This article is from the WineMaking FAQ, by malak@CAM.ORG (Don Buchan) with numerous contributions by others.
The US and Britain (and some of the Commonwealth) use the Imperial
system (though Britain & the Commonwealth also uses the metric system),
but the measurements of each system are not necessarily equal to those
of the other. As a rule, the whole world except the US uses the Metric
Some information found here was found in Alan Marshall's FAQ on sizes,
which can be found at:
ftp.stanford.edu in /pub/clubs/homebrew/beer/rfdb/beer-capacity.faq
Bottle: 750 mL, 1/5 USG, 1/6 imp. gal.
Barrel: 36 imp. gal. (UK barrel), 30 and 6/11 USG (US barrel)
* note that there are various other standard and non-standard barrel
Carboy: 5 imp. gal., 6.5 USG or occasionally 4.2 imp. gal, 5 USG
Demijohn: 25 to 64 litres, 5.6 to 14.2 imp. gal, 6.6 to 16.9 USG
1 Imp. gal (160 Imp fl oz) = 4.546 litres
1 US gal (128 US fl oz) = 3.785 litres
Magnum: 1.5 litres, 2/5 USG, 1/3 imp. gal.
The usual primary fermentor used by home winemakers holds 6.5 imp. gal.
(7.74 USG; 29.25 litres) and the secondary fermentor is a carboy.
However, there are various other sizes, such as 5 USG, as well as
various other sizes that are convenient to the individual.
[I need proper conversions. Am I right with the imperial?]
Volume Vol. Vol. Name imp. US 375ml 13.2 oz. 12.7 oz. fillette 750ml 26.4 oz. 25.4 oz. bottle (fifth) 1000ml 35.2 oz. 33.8 oz. litre 1500ml 52.8 oz. 50.7 oz. magnum 2250ml 79.2 oz. 76.1 oz. tappit 3000ml 105.6 oz. 101.5 oz. double magnum 4500ml 158.4 oz. 152.2 oz. jeroboam 6000ml 211.2 oz. 202.9 oz. imperial
1 imp. fl. oz = 28.4 ml 1 imp. pint = 20 imp. fl. oz 1 imp. quart = 40 imp. fl. oz 1 imp. gallon = 160 imp. fl. oz 1 US fl. oz. = 29.57 ml 1 US pint = 16 US fl. oz. 1 US quart = 32 US fl. oz. 1 USG = 128 US fl. oz.