Convert Firkins to Imperial Gallons

Convert Firkins (fir) to Imperial Gallons (UK gal) instantly and accurately.

Conversion Formula

UK gal = fir × 7.494067662

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.

About Imperial Gallons

A US imperial gallon (UK gal) = exactly 8 imperial pints or 10 lb of pure water at 62°F ≈ 4.546 L - about 20% larger than the US liquid gallon (3.785 L). The weight-based definition made it verifiable with simple scales. Still the legal fuel measure in the Cayman Islands and other British Overseas Territories. UK mpg ratings use imperial gallons: 50 UK mpg ≈ 42 US mpg. 1 UK gal ≈ 4.546 L.

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