Math olympiads
International
IMOInternational Mathematical OlympiadThe oldest of the international science olympiads, first held in Brașov in 1959 with seven countries.
EGMOEuropean Girls' Mathematical OlympiadFirst held at Murray Edwards College, Cambridge, in April 2012, from an idea Geoff Smith had at Christmas 2009, with the support of the college and the United Kingdom Mathematics Trust.
APMOAsian Pacific Mathematics OlympiadThe olympiad of the countries of the Pacific Rim, first held in 1989.
OIMOlimpíada Iberoamericana de MatemáticaThe olympiad of the Spanish- and Portuguese-speaking countries of the Americas and the Iberian Peninsula.
Cone SulOlimpíada de Matemática do Cone SulThe olympiad of South America's Southern Cone, first held in Uruguay in 1988 and hosted in turn by its member countries since.
Baltic WayBaltic Way Mathematical Team ContestA team contest for the countries around the Baltic Sea, together with Norway and Iceland, held every year since the first in Riga in 1990.
OMCPLPOlimpíada de Matemática da Comunidade dos Países de Língua PortuguesaThe olympiad of the Portuguese-speaking countries, first held in 2011 and sat in Portuguese.
National
OBMOlimpíada Brasileira de MatemáticaBrazil's national olympiad, first organised by the Brazilian Mathematical Society in 1979.
OBMEPOlimpíada Brasileira de Matemática das Escolas PúblicasCreated in 2005 and run by IMPA, the Instituto de Matemática Pura e Aplicada, with funding from Brazil's ministries of education and of science and technology.
USAMOUSA Mathematical OlympiadThe United States of America Mathematical Olympiad, run by the Mathematical Association of America and first held in 1972.
USA Math TSTUSA IMO Team Selection TestsThe tests that choose the United States teams for the IMO and EGMO, run by the Mathematical Association of America.
CMOCanadian Mathematical OlympiadCanada's national olympiad, first held in 1969 and written by invitation of the Canadian Mathematical Society.
BMOBritish Mathematical OlympiadThe United Kingdom's national mathematical olympiad, first held in 1965 and today run by the UK Mathematics Trust.
HK PrelimIMO Hong Kong Preliminary Selection ContestThe first round of selection for Hong Kong's IMO team, set by the International Mathematical Olympiad Hong Kong Committee and today organised with the Hong Kong Academy for Gifted Education.
OPMOlimpíada Paulista de MatemáticaThe São Paulo state olympiad, first held in 1977 on the initiative of the physicist Shigueo Watanabe and the Academia de Ciências do Estado de São Paulo, two years before the national OBM.
Open
Coming
Balkan MORMM
China's national olympiads (the CMO, the team selection tests, the CGMO and the National High School League) are not archived: no official archive of past papers exists, and the copies that circulate are unofficial re-typesets and commercial books.