The International Carbon Dioxide Conference (ICDC) is an international conference series dedicated to understanding the global carbon cycle and its role in the Earth system.

The first conference was held in 1981, and the conference has taken place every four years, with the exception of the 2021 meeting, which was delayed until 2024 because of the COVID-19 pandemic. The first two conferences, held in Bern in 1981 and Kandersteg in 1985, were organised by Hans Oeschger, Charles David Keeling and Ulrich Siegenthaler, pioneers in ice-core CO₂ reconstructions, atmospheric CO₂ measurements and carbon-cycle modelling. ICDC11 took place in Manaus, Brazil, in 2024.

The ICDC series has taken place in different locations around the world, providing an international forum for researchers to share the latest developments in carbon-cycle science.

ICDC12 will continue this history and will be the first time the conference has been held in the UK.

ICDC12 will take place at the University of Exeter, UK, from 21–25 June 2027, bringing together the international carbon-cycle community to share the latest research, exchange ideas and explore new directions for the field.