List of UTC timing centers is a list of over 70 recognized maintainers of atomic clocks around the world from which UTC is calculated. [1] Below are links to some of the more notable time centers which contribute to the calculation of UTC. UTC is calculated by the International Bureau of Weights and Measures (BIPM) [2] using weighted averages of the various times as reported by these 70+ listed timing centers. [3] [4] BIPM lists the time differences between the UTC timing centers in a monthly publication called Circular T, which contains the most up to date list of contributors to UTC. [5]
| Acronym | Full name | Country | City | Former acronym | CIPM MRA signatory | Start year | Stop year |
|---|---|---|---|---|---|---|---|
| AGGO | Argentinian-German Geodetic Observatory | Argentina | La Plata | TCC | 2002 | ||
| AOS | Astrogeodynamical Observatory, Space Research Centre P.A.S. | Poland | Borowiec | 1988 | |||
| APL | Applied Physics Laboratory | United States of America | Laurel | 1978 | |||
| AUS | National Measurement Institute | Australia | Sydney | NMIA | 1973 | ||
| BEV | Bundesamt für Eich- und Vermessungswesen | Austria | Wien | BEV | 1975 | ||
| BFKH | Government Office of Capital City of Budapest, Metrology and Technical Supervisory Department | Hungary | Budapest | MKEH | BFKH | 1974 | |
| BIM | Bulgarian Institute of Metrology | Bulgaria | Sofiya | NMC | BIM | 1991 | |
| BIRM | Beijing Institute of Radio Metrology and Measurement | P.R. China | Beijing | 1995 | |||
| BOM | Bureau of Metrology of Macedonia | Macedonia | Skopje | BOM | 2017 | ||
| BSJ | Bureau of Standards Jamaica | Jamaica | Kingston | BSJ | 2024 | ||
| BY | Belarussian State Institute of Metrology | Belarus | Minsk | BelGIM | 2007 | ||
| CAO | Stazione Astronomica di Cagliari (Cagliari Astronomical Observatory) | Italy | Cagliari | 1982 | |||
| CH | Federal Institute of Metrology (METAS) | Switzerland | Bern | METAS | 1972 | ||
| CNES | Centre National d'Etudes Spatiales | France | Toulouse | 2016 | |||
| CNM | Centro Nacional de Metrologia | Mexico | Queretaro | CENAM | 1996 | ||
| CNMP | Centro Nacional de Metrología de Panamá (CENAMEP) | Panama | Panama | CENAMAP AIP | 2003 | ||
| DFM | Dansk Fundamental Metrologi (DFM A/S) | Denmark | Hørsholm | DFM | 2022 | ||
| DFNT | Laboratoire de Métrologie de la Direction Générale des Transmissions et de l'Informatique (DEF-NAT) | Tunisia | Tunis | DEF-NAT | 2014 | ||
| DLR | Deutsches Zentrum für Luft - und Raumfahrt (German Aerospace Centre) | Germany | Oberpfaffenhofen | 1996 | |||
| DMDM | Directorate of Measures and Precious Metals | Serbia | Belgrade | ZMDM | 1983 | ||
| DTAG | Deutsche Telekom AG | Germany | Frankfurt/M | 1981 | |||
| EIM | Hellenic Institute of Metrology | Greece | Thessaloniki | EIM | 2007 | ||
| ESA | European Space Agency | The Netherlands | Noordwijk | ESTC | ESA | 2012 | |
| HKO | Hong Kong Observatory | Hong Kong (China) | Hong Kong | 2004 | |||
| IBM | Instituto Boliviano De Metrologia | Bolivia | La Paz | IBMETRO | 2023 | ||
| ICE | Laboratorio Costarricense de Metrologia | Costa Rica | San José | LAMETRO-ICE | 2017 | ||
| IDN | Standardization Agency of Indonesia | Indonesia | Jakarta | KIM | SNSU-BSN | 2008 | |
| IFAG | Bundesamt für Kartographie und Geodäsie (Federal Agency for Cartography and Geodesy) | Germany | Wettzell | 1988 | |||
| IFZG | State Office for Metrology | Croatia | Zagreb | DZM | 2024 | ||
| IGNA | Instituto Geográfico Nacional | Argentina | Buenos Aires | 1969 | |||
| IMBH | Institute of Metrology of Bosnia and Herzegovina | Bosnia and Herzegovina | Sarajevo | IMBIH | 2015 | ||
| INCP | Instituto Nacional de Calidad (INACAL) of Peru | Peru | Lima | INACAL | 2016 | ||
| INM | Instituto Nacional de Metrología of Colombia | Colombia | Bogota D.C. | INM(CO) | 2017 | ||
| INPL | National Physical Laboratory of Israel | Israel | Jerusalem | INPL | 1988 | ||
| INTI | Instituto Nacional de Tecnología Industrial | Argentina | Buenos Aires | INTI | 2008 | ||
| INXE | National Institute for Metrology, Quality and Technology (INMETRO) | Brazil | Rio de Janeiro | INMETRO | 2012 | ||
| IPQ | Instituto Portugues da Qualidade | Portugal | Caparica | IPQ | 1995 | ||
| IT | Istituto Nazionale di Ricerca Metrologica (INRIM) | Italy | Torino | IEN | INRIM | 1970 | |
| JATC | Joint Atomic Time Commission | P.R. China | Lintong | 1988 | |||
| JV | Justervesenet | Norway | Kjeller | JV | 2003 | ||
| KEBS | Kenya Bureau of Standards | Kenya | Nairobi | KEBS | 2012 | 2019 | |
| KRIS | Korea Research Institute of Standards and Science (KRISS), | Rep. of Korea | Daejeon | KSRI | KRISS | 1988 | |
| KZ | Kazakhstan Institute of Standardization and Metrology | Kazakhstan | Astana | KazStandard | 2008 | ||
| LDS | University of Leeds | United Kingdom | Leeds | 1991 | 2009 | ||
| LRTE | Laboratório de Referência de Tempo e Espaço | Brazil | Sao Carlos | 2018 | |||
| LT | Center for Physical Sciences and Technology (VMT/FTMC) | Lithuania | Vilnius | FTMC | 2001 | ||
| LUX | Bureau Luxembourgeois de Métrologie (ILNAS) | Luxembourg | Belvaux | ILNAS | 2018 | ||
| LV | Latvian National Metrology Centre | Latvia | Riga | LATMB | 2007 | 2021 | |
| MASM | Mongolian Agency for Standardization and Metrology | Mongolia | Ulaanbaatar | MASM | 2013 | ||
| MBM | Bureau of Metrology - Laboratory for time and frequency | Montenegro | Podgorica | BMM | 2014 | ||
| MIKE | VTT Technical Research Centre of Finland Ltd, Centre for Metrology | Finland | Espoo | MIKES | 1978 | ||
| MSL | Measurement Standards Laboratory | New Zealand | Lower Hutt | MSL | 1984 | ||
| MTC | MAKKAH Time Centre - King Abdulah Centre for Crescent Observations and Astronomy | Saudi Arabia | Makkah | 2012 | |||
| NAO | National Astronomical Observatory | Japan | Mizusawa | NAOM | 1969 | ||
| NICT | National Institute of Information and Communications Technology | Japan | Tokyo | CRL | NICT | 1969 | |
| NIM | National Institute of Metrology | P.R. China | Beijing | NIM | 1980 | ||
| NIMB | National Institute of Metrology | Romania | Bucharest | INM | 2002 | ||
| NIMT | National Institute of Metrology (Thailand) | Thailand | Pathumthani | NIMT | 2001 | ||
| NIS | National Institute for Standards | Egypt | Cairo | NIS | 1972 | ||
| NIST | National Institute of Standards and Technology | United States of America | Boulder | NBS | NIST | 1969 | |
| NMIJ | National Metrology Institute of Japan | Japan | Tsukuba | NRLM | NMIJ AIST | 1980 | |
| NMLS | National Metrology Laboratory of SIRIM Berhad | Malaysia | Sepang | NMIM | 2002 | ||
| NPL | National Physical Laboratory | United Kingdom | Teddington | NPL | 1969 | ||
| NPLI | National Physical Laboratory | India | New-Delhi | NPLI | 1988 | ||
| NRC | National Research Council of Canada | Canada | Ottawa | NRC | 1969 | ||
| NRL | U.S. Naval Research Laboratory | United States of America | Washington DC | 2007 | |||
| NSAI | National Standards Authority of Ireland's National Metrology Laboratory (NSAI NML) | Ireland | Dublin | NSAI NML | 2020 | ||
| NTSC | National Time Service Center of China | P.R. China | Lintong | CSAO | 1980 | ||
| ONBA | Observatorio Naval | Argentina | Buenos Aires | 1970 | |||
| ONRJ | Observatório Nacional | Brazil | Rio de Janeiro | ON/DSHO | 1972 | ||
| OP | Observatoire de Paris/Laboratoire Temps Espace | France | Paris | LPTF,LNE-SYRTE | LNE-OP | 1968 | |
| ORB | Observatoire Royal de Belgique | Belgium | Bruxelles | 1972 | |||
| PL | Consortium of laboratories in Poland | Poland | Warszawa | GUM | GUM | 1977 | |
| PTB | Physikalisch-Technische Bundesanstalt | Germany | Braunschweig | PTB | 1968 | ||
| ROA | Real Instituto y Observatorio de la Armada | Spain | San Fernando | OMSF | ROA | 1989 | |
| SASO | Saudi Standards, Metrology and Quality Organization | Saudi Arabia | Riyadh | SASO-NMCC | 2013 | ||
| SCL | Standards and Calibration Laboratory | Hong Kong (China) | Hong Kong | SCL | 1996 | ||
| SG | National Metrology Centre - Agency for Science, Technology and Research (A*STAR) | Singapore | Singapore | PSB | NMC, A*STAR | 1981 | |
| SIQ | Slovenian Institute of Quality and Metrology | Slovenia | Ljubljana | MIRS/SIQ/Metrology | 2007 | ||
| SL | Measurement Units, Standards and Services Department (MUSSD) | Sri Lanka | Colombo | MUSSD | 2018 | ||
| SMD | Metrology Division of the Quality and Safety Department - Scientific Metrology | Belgium | Bruxelles | SMD | 2009 | ||
| SMU | Slovenský Metrologický Ústav (Slovak Institute of Metrology) | Slovakia | Bratislava | SMU | 1998 | ||
| SP | Research Institutes of Sweden AB (RISE) | Sweden | Boras | RISE | 1978 | ||
| SU | Russian metrological institute of technical physics and radio engineering (FSUE VNIIFTRI") " | Russian Federation | Moskva | VNIIFTRI | 1969 | ||
| TL | Telecommunication Laboratories | Chinese Taipei | Chung-Li | TL | 1972 | ||
| TP | Institute of Photonics and Electronics, Czech Academy of Sciences (IPE/ASCR) | Czech Republic | Praha | IPE/ASCR | 1968 | ||
| TUG | Technische Universität | Austria | Graz | 1977 | 2000 | ||
| UA | National Scientific Centre Institute of Metrology"" | Ukraine | Kharkiv | NSC IM | 2006 | ||
| UAE | Emirates Metrology Institute (EMI/UAE) | The United Arab Emirates | Abu Dhabi | EMI | 2017 | ||
| UME | Ulusai Metroloji Enstitüsü, Marmara Research Centre, (National Metrology Institute) | Türkiye | Gebze-Kocaeli | UME | 1994 | ||
| USNO | U.S. Naval Observatory | United States of America | Washington DC | 1968 | |||
| UTE | Administración Nacional de Usinas y Transmisiones | Uruguay | Montevideo | UTE | 2023 | 2024 | |
| UZ | Uzbek National Institute of Metrology of Uzstandard Agency | Uzbekistan | Tashkent | UzNIM | 2023 | ||
| VMI | Vietnam Metrology Institute | Vietnam | Ha Noi | VMI-STAMEQ | 2008 | ||
| VSL | VSL, Dutch Metrology Institute | The Netherlands | Delft | VSL | 1973 | ||
| ZA | National Metrology Institute of South Africa (NMISA) | South Africa | Pretoria | CSIR | NMISA | 1972 |