Portuguese units of measurement

King Manuel I, who fixed the country's measurement standards, in 1499-1504.

Portuguese customary units were used in Portugal, Brazil and other parts of the Portuguese Empire until the adoption of the metric system in the 19th century.

The official system of units in use in Portugal from the 16th to the 19th century was the system introduced by king Manuel I around 1499-1504. The most salient aspect of this reform was the distribution of bronze weight standards (nesting weight piles) to the towns of the kingdom. The reform of weights is unparalled in Europe until this time, due to the number of distributed standards (hundreds), the size (64 to 256 marcs) and the elaborate decoration.

In 1575, king Sebastião distributed bronze standards of capacity measures to the main towns. The number of distributed standards was smaller and uniformity of capacity measures was never achieved.

In 1814, Portugal was the second country in the world – after France – to officially adopt the metric system. The system then adopted used the names of the Portuguese traditional units instead of the original French names (e.g.: vara for metre; canada for litre; and libra for kilogram). However, several difficulties prevented the implementation of the new system and the old Portuguese customary units continued to be used, both in Portugal and in Brazil (which became an independent country in 1822).

The metric system was finally adopted by Portugal and its colonies in 1852, this time using the original names of the units. Brazil replaced Portuguese customary units with the metric system in 1862.

Route units

Portuguese name	English name	Subdivides in	Equivalence in Léguas de 20 ao grau	Metric equivalence
Légua de 18 ao grau	League of 18 to the degree			6173 m
Légua de 20 ao grau	League of 20 to the degree	3 milhas geográficas	1	5555 m
Milha geográfica	Geographical mile		1/3	1851 m

Length units

Portuguese name	English name	Subdivides in	Equivalence in Varas	Metric equivalence
Braça	Fathom	2 varas	2	2.2 m
Toesa	Toise	6 pés	14⁄5	1.98 m
Passo geométrico	Geometrical pace	5 pés	11⁄2	1.65 m
Vara	Yard	5 palmos	1	1.1 m
Côvado	Cubit	3 palmos	3/5	0.66 m
Pé	Foot	12 polegadas	3/10	0.33 m
Palmo de craveira	Span	8 polegadas	1/5	0.22 m
Polegada	Inch	12 linhas	1/40	27.5 mm
Linha	Line	12 pontos	1/480	2.29 mm
Ponto	Point		1/5760	0.19 mm

Weight units

Portuguese name	English name	Subdivides in	Equivalence in Arráteis	Metric equivalence
Tonelada	Tonne	13.5 quintais	1728	793.152 kg
Quintal	Hundredweight	4 arrobas	128	58.752 kg
Arroba	Arroba	32 arráteis	32	14.688 kg
Arrátel	Pound	4 quartas	1	0.459 kg
Marco	Mark	8 onças	1/2	0.22950 kg
Quarta	Fourth	4 onças	1/4	0.11475 kg
Onça	Ounce	8 oitavas	1/16	28.6875 g
Oitava	Dram	3 escrópulos	1/128	3.5859 g
Escrópulo	Scruple	24 grãos	1/384	1.1953 g
Grão	Grain		1/9216	0.0498 g

Liquid volume units (for Lisbon)

Portuguese name	English name	Subdivides in	Equivalence in canadas	Metric equivalence
Tonel	Cask	2 pipas	600	840 l
Pipa	Barrel	25 almudes	300	420 l
Almude		2 potes	12	16.8 l
Pote	Pot	6 canadas	6	8.4 l
Canada		4 quartilhos	1	1.4 l
Quartilho	Pint	2 meios quartilhos	1/4	0.35 l
Meio quartilho			1/8	0.175 l

See also

• Alqueire
• Spanish customary units

References

• Barroca, M.J. (1992) «Medidas-Padrão Medievais Portuguesas», Revista da Faculdade de Letras. História, 2ªa Série, vol. 9, Porto, pp. 53–85.
• Dicionário Enciclopédico Lello Universal, Porto: Lello & Irmão, 2002.
• Monteverde, Emilio Achilles (1861) Manual Encyclopedico para Uzo das Escolas de Instrucção Primaria, Lisboa: Imprensa Nacional.
• Paixão, Fátima & Jorge, Fátima Regina (2006) «Success and constraints in the adoption of the metric system in Portugal», The Global and the Local: The History of Science and the Cultural Integration of Europe. Proceedings of the 2nd ICESHS (Cracow, Poland 6-9, 2006).
• Seabra Lopes, L. (2003) "Sistemas Legais de Medidas de Peso e Capacidade, do Condado Portucalense ao Século XVI", Portugalia: Nova Série, XXIV, Faculdade de Letras, Porto, p. 113-164.
• Seabra Lopes, L. (2005) "A Cultura da Medição em Portugal ao Longo da História", Educação e Matemática, nº 84, Setembro-Outubro de 2005, p. 42-48.
• Seabra Lopes, L. (2018) "As Pilhas de Pesos de Dom Manuel I: Contributo para a sua Caracterização, Inventariação e Avaliação", Portugalia: Nova Série, vol. 39, Universidade do Porto, p. 217-251.