What is a standard drink
A standard drink contains approximately 10 grams of pure alcohol. There are different quantities of alcohol in each major type of alcoholic drink; beer, wine and spirits. Each of the drinks displayed below has approximately the same amount of alcohol and are therefore called standard drinks.
Each of these drinks contains approximately the same amount of alcohol i.e. 10 grams. If you drink a small glass of port you would be consuming the same amount of alcohol as a pot of beer. Similarly, a typical "Scotch and Coke" would be the same as drinking a 100ml glass of wine.
It is important to be aware that a standard drink and a standard size glass are not the same thing. Wine is often served in a 200ml glass. This quantity of wine contains 20 grams of alcohol (i.e. 2 standard drinks).
Cocktails can contain multiple standard drinks.
In Australia all bottles, cans and casks of liquor must, by law, state the number of standard drinks they contain and the percentage of alcohol by volume in the container.