Metric foot

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For the poetical term, see foot (prosody).

A metric foot, is a nickname occasionally used in the United Kingdom for a length of 300 millimetres (30 cm). A metric foot can be divided into twelve "metric inches" of 25 millimetres (2.5 cm). The metric foot and inch are therefore 4.8 and 0.4 millimetres (or about ¹⁄₆₀) shorter than an imperial foot and inch respectively.

The term "metric foot" does not appear in any British Standard. The practice of chosing multiples of 300 mm and 600 mm as preferred dimensions in the construction industry originated from the international standard on modular coordination (ISO 2848). These numbers were chosen because of their large number of divisors. Any multiple of 600 mm can be evenly divided into 2, 3, 4, 5, 6, 8, 10, 12, 15, 20, 24, 25, 30, etc. parts. This makes metric modular-coordination lengths much easier to use with mental arithmetic than inch-foot lengths.

While the term "metric foot" is still occasionally used in the United Kingdom, in particular in the timber trade, dimensions are most likely to be quoted exclusively in metric units today.

The sizes of the studios at BBC Television Centre in London, first opened in 1960, are all specified and measured up in metric feet – a contrast to film stages where imperial feet and inches prevail.

Historically in France, under the mesures usuelles system (intermediary between traditional French units and metric units), a metric foot was exactly 1/3 of a metre.