Convert Fluid Ounces to Firkins

Convert Fluid Ounces (fl oz) to Firkins (fir) instantly and accurately.

Conversion Formula

fir = fl oz × 0.0008680555556

About Fluid Ounces

A fluid ounce (fl oz) is a US customary volume unit equal to 1/8 of a cup or 1/128 of a gallon - approximately 29.574 mL. Despite sharing a name with the weight unit 'ounce', fluid ounces measure volume, not mass. In the US, beverages are universally labeled in fluid ounces: a standard can of soda is 12 fl oz, a standard wine pour is 5 fl oz, and a shot of spirits is 1.5 fl oz. Note that the UK imperial fluid ounce (28.413 mL) differs slightly from the US fluid ounce (29.574 mL) - a common source of confusion in international recipes and product comparisons.

About Firkins

A firkin (fir) ≈ 34.07 L (9 US gallons) - the most common cask for British real-ale delivery (9 imperial gallons = 40.91 L). A busy pub cellar cycles through several firkins per week. Craft breweries stage 'firkin tappings' of limited experimental ales. The name comes from Middle Dutch 'vierdekijn' (little fourth), as a firkin was one quarter of a barrel. 1 fir = 9 US gal ≈ 34.07 L.

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