Convert Firkins to Acre-Feet

Convert Firkins (fir) to Acre-Feet (ac ft) instantly and accurately.

Firkins (fir)
Acre-Feet (ac ft)

Conversion Formula

ac ft = fir × 2.761994949e-5

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 Acre-Feet

An acre-foot (ac ft) = the volume covering 1 acre to 1 ft depth ≈ 1,233.5 m³ (325,851 US gal). Almost exclusively used in US water resource management. California's Lake Shasta: 4.55 million ac ft at capacity. A typical US household uses ~0.5-1 ac ft/year. Water rights on the Colorado and Sacramento rivers are traded in acre-feet. 1 ac ft ≈ 1,233.5 m³.

Quick Reference Table

Firkins (fir)Acre-Feet (ac ft)
1 fir2.762 × 10-5 ac ft
2 fir5.524 × 10-5 ac ft
5 fir0.0001381 ac ft
10 fir0.000276199 ac ft
25 fir0.000690499 ac ft
50 fir0.001381 ac ft
100 fir0.00276199 ac ft

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