International Convention amending the Convention concluded at Paris on 20 May 1875 ensuring the international unification and perfection of the metric system and the Regulations annexed to that Convention

Party

Uzbekistan added

• Ratification: 16-12-2025 (A)
• Entry into force: 16-12-2025
• Reservations / Declarations: No
• Objections: No

Party

United Kingdom modified

• Signature: 06-10-1921
• Ratification: 21-02-1923
• Entry into force: 21-02-1923

General information

• Entry into force: 05-02-1923

Kingdom part

Netherlands (in Europe)

• Entry into force: 01-01-1929

Party

Argentina

• Signature: 06-10-1921

Australia

• Ratification: 27-11-1947 (A)
• Entry into force: 27-11-1947

Austria

• Signature: 06-10-1921
• Ratification: 15-12-1926 (R)
• Entry into force: 15-12-1926

Belarus

• Ratification: 13-01-2020 (A)
• Entry into force: 13-01-2020

Belgium

• Signature: 06-10-1921
• Ratification: 28-07-1923 (R)
• Entry into force: 28-07-1923

Brazil

• Ratification: 14-04-1954 (A)
• Entry into force: 14-04-1954

Bulgaria

• Signature: 06-10-1921
• Ratification: 27-08-1925 (R)
• Entry into force: 27-08-1925

Cameroon

• Ratification: 07-10-1970 (A)
• Entry into force: 07-10-1970

Canada

• Signature: 06-10-1921
• Ratification: 21-02-1923 (R)
• Entry into force: 21-02-1923

Chile

• Signature: 06-10-1921

China

• Ratification: 20-05-1977 (A)
• Entry into force: 20-05-1977

Colombia

• Ratification: 06-02-2013 (A)
• Entry into force: 06-02-2013

Costa Rica

• Ratification: 05-09-2022 (R)
• Entry into force: 05-09-2022

Croatia

• Ratification: 23-12-2008 (A)
• Entry into force: 23-12-2008

Czech Republic

• Ratification: 13-01-1993 (A)
• Entry into force: 13-01-1993

Czechoslovakia (<01-01-1993)

• Ratification: 21-06-1922 (A)
• Entry into force: 21-06-1922

Democratic People's Republic of Korea

• Ratification: 07-05-1982 (A)
• Entry into force: 07-05-1982

Denmark

• Signature: 06-10-1921
• Ratification: 10-02-1923 (R)
• Entry into force: 10-02-1923

Ecuador

• Ratification: 06-08-2019 (A)
• Entry into force: 06-08-2019

Egypt

• Ratification: 02-11-1962 (A)
• Entry into force: 02-11-1962

Finland

• Signature: 06-10-1921
• Ratification: 31-08-1923 (R)
• Entry into force: 31-08-1923

France

• Signature: 06-10-1921
• Ratification: 01-08-1928 (R)
• Entry into force: 01-08-1928

Germany

• Signature: 06-10-1921
• Ratification: 30-01-1928 (R)
• Entry into force: 30-01-1928

Greece

• Ratification: 19-03-2001 (A)
• Entry into force: 19-03-2001

Hungary

• Signature: 06-10-1921
• Ratification: 14-08-1925 (R)
• Entry into force: 14-08-1925

India

• Ratification: 11-01-1957 (A)
• Entry into force: 11-01-1957

Indonesia

• Ratification: 30-09-1960 (A)
• Entry into force: 30-09-1960

Iran

• Ratification: 25-02-1975 (A)
• Entry into force: 25-02-1975

Iraq

• Ratification: 20-08-2013 (A)
• Entry into force: 20-08-2013

Ireland

• Ratification: 29-10-1925 (A)
• Entry into force: 29-10-1925

Israel

• Ratification: 07-05-1985 (A)
• Entry into force: 07-05-1985

Italy

• Signature: 06-10-1921
• Ratification: 07-08-1924 (R)
• Entry into force: 07-08-1924

Japan

• Signature: 06-10-1921
• Ratification: 30-12-1926 (R)
• Entry into force: 30-12-1926

Kenya

• Ratification: 01-01-2010 (A)
• Entry into force: 01-01-2010

Lithuania

• Ratification: 16-04-2015 (A)
• Entry into force: 16-04-2015

Malaysia

• Ratification: 03-09-2001 (A)
• Entry into force: 03-09-2001

Mexico

• Signature: 06-10-1921
• Ratification: 15-04-1927 (R)
• Entry into force: 15-04-1927

Montenegro

• Ratification: 24-01-2018 (A)
• Entry into force: 24-01-2018

Morocco

• Ratification: 24-05-2019 (A)
• Entry into force: 24-05-2019

Netherlands, the Kingdom of the

• Ratification: 01-01-1929 (A)
• Entry into force: 01-01-1929

New Zealand

• Ratification: 29-05-1991 (A)
• Entry into force: 29-05-1991

Norway

• Signature: 06-10-1921
• Ratification: 03-08-1923 (R)
• Entry into force: 03-08-1923

Pakistan

• Ratification: 12-07-1973 (A)
• Entry into force: 12-07-1973

Peru

• Ratification: 26-07-1937 (R)
• Entry into force: 26-07-1937

Poland

• Ratification: 12-05-1925 (A)
• Entry into force: 12-05-1925

Portugal

• Signature: 06-10-1921
• Ratification: 17-06-1926 (R)
• Entry into force: 17-06-1926

Republic of Korea, the

• Ratification: 28-07-1959 (A)
• Entry into force: 28-07-1959

Romania

• Signature: 06-10-1921
• Ratification: 11-02-1926 (R)
• Entry into force: 11-02-1926

Russian Federation

• Ratification: 12-08-1925 (A)
• Entry into force: 12-08-1925

Saudi Arabia

• Ratification: 11-02-2011 (A)
• Entry into force: 11-02-2011

Serbia

• Ratification: 09-04-2001 (A)
• Entry into force: 09-04-2001

Singapore

• Ratification: 20-06-1994 (A)
• Entry into force: 20-06-1994

Slovakia

• Ratification: 13-01-1993 (A)
• Entry into force: 13-01-1993

Slovenia

• Ratification: 23-03-2016 (A)
• Entry into force: 23-03-2016

South Africa

• Ratification: 31-07-1964 (A)
• Entry into force: 31-07-1964

Spain

• Signature: 06-10-1921
• Ratification: 31-12-1926 (R)
• Entry into force: 31-12-1926

Sweden

• Signature: 06-10-1921
• Ratification: 16-02-1923 (R)
• Entry into force: 16-02-1923

Switzerland

• Signature: 06-10-1921
• Ratification: 05-02-1923 (R)
• Entry into force: 05-02-1923

Thailand

• Signature: 06-10-1921
• Ratification: 25-11-1950 (R)
• Entry into force: 25-11-1950

Türkiye

• Ratification: 01-01-1933 (A)
• Entry into force: 01-01-1933

Ukraine

• Ratification: 07-08-2018 (A)
• Entry into force: 07-08-2018

United Arab Emirates

• Ratification: 27-04-2015 (A)
• Entry into force: 27-04-2015

United Kingdom

• Ratification: 12-02-1923 (R)
• Entry into force: 12-02-1923

United States of America

• Signature: 06-10-1921
• Ratification: 24-10-1923 (R)
• Entry into force: 24-10-1923

Uruguay

• Signature: 06-10-1921
• Ratification: 02-12-1925 (R)
• Entry into force: 02-12-1925

Venezuela

• Ratification: 18-11-1960 (A)
• Entry into force: 18-11-1960
• Termination: 14-11-2018

Yugoslavia (< 25-06-1991)

• Ratification: 10-11-1929 (R)
• Entry into force: 10-11-1929