For all intents and purposes whisky is the most potent form a alcohol you can purchase in a store. By definition to be called whisky it must be at least 40% alcohol. Almost all whisky is 40% - you can buy cask strength whisky at specialist retailers online going up as high as 60%.
So lets assume 40% as being the standard whisky alcohol content - which is very reasonable. We find that a litre bottle of whisky contains 40 units, a 70cl contains 28 units and a single measure (25ml) contains 1 unit. Take as a bench mark that a pint is between 2.3 and 2.8 units.
The way I like to think about the potency of whisky is to visualise it as so:
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| You remember what its like to drink a whole bottle of wine? |
However when you go out to the pub you are better to drink whisky measures than glasses of wine (1.25-1.75 units) or pints (2.3-2.8 units) as a measure of whisky is small and contains the least alcohol (1 unit) of almost all the other drinks you can order.
