The amount of beer a yard glass can hold varies; although a yard glass is, by name, 1 yard long, the diameter of a yard glass is unstandardized. Encyclopedia Britannica describes a yard glass as holding about 16 ounces; however, Libbey markets a "half yard" glass that holds 32 ounces.
The Guinness Book of World Records defines a yard of ale as 1.42 liters, or about 48 ounces, for its purposes. In general, yard glasses hold considerably more than a standard beer glass. They are commonly employed for drinking games in the United Kingdom. A related piece of glassware is the beer boot, a beer glass in the shape of a boot that commonly holds 33 ounces or more.