Pieds Du Roi to Feet (pied to ft)

1 pied du roi equals 1.065746014 feet (rounded).

1 pied du roi = 1.065746014 feet

How to convert pieds du roi to feet

To convert pieds du roi to feet, multiply the number of pieds du roi by 1.065746014. The factor is rounded to 10 significant digits. To go the other way, multiply feet by 0.9383098667 (rounded).

feet = pieds du roi × 1.065746014

Example: 10 pieds du roi = 10.65746014 feet.

About these units

Pied Du Roi (pied)

French (Ancien Régime)Historical unit (no longer in standard use)

The 'king's foot' of the French Ancien Régime, about 32.48 cm; 12 pouces. About 6.6% longer than the English foot.

King's foot is the literal meaning of the name, and the unit was reputed to descend, with little change, from the measures of Charlemagne, which in turn drew on Byzantine and Roman practice. For about a thousand years it stayed close to the same length, though the surviving standards disagree slightly: the foot of the old toise de l'Écritoire is given as 326.6 millimetres, against about 324.8 for the later royal foot.

The figure now used for the pied du roi is 4500/13853 metre, about 32.48 centimetres or 1.066 English feet. This ratio comes from the 1799 law that defined the metre in terms of the Toise of Peru. It was divided into 12 pouces and 144 lignes, while six pieds made one toise.

Wikipedia notes that its own sources vary on details of the standards. The iron toise at the Grand Châtelet was bent before 1668 and replaced by a bar roughly 0.5 percent shorter, which shows how much a nominally fixed unit could drift. Quebec's pied, still seen in land records, is about four parts per million smaller than the French original.

1 pied du roi = 0.324839385 meters (approximately).

Sources: Wikipedia: Pied du roi; Wikipedia: Toise; Wikipedia: Traditional French units of measurement

Foot (ft)

US & ImperialCurrent unit

12 inches. Defined as exactly 0.3048 meters. Still the standard unit for height, altitude in aviation and room dimensions in the US and UK.

Human anatomy supplied the idea: an adult foot is roughly 15 percent of body height. Ancient cultures turned that into standards, but not the same one. The Greek pous was about 302 mm, the standard Roman pes about 295.7 mm, and a Harappan foot of about 335 mm has been reported from the Indus Valley. Historically, a foot fell somewhere between about 250 and 335 mm. Charlemagne tried to standardize units around 790 with little lasting success, and in 1593 English law fixed the statute mile at 5,280 feet.

The modern foot dates from the 1959 International Yard and Pound Agreement, which defined the yard as exactly 0.9144 meter and so the foot as exactly 0.3048 meter; the UK adopted it on 1 January 1964. The US survey foot, defined in 1893 as 1200/3937 meter, was deprecated on 31 December 2022. Feet remain in everyday use for height and rooms in the US, and ISO shipping containers are defined in them. Aviation altitudes use them too: flight level 330 means 33,000 feet.

1 foot = 0.3048 meters (exactly).

Sources: Wikipedia: Foot (unit); Wikipedia: Mile; NIST Guide to the SI, Appendix B.8: conversion factors

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