Carbon dioxide corrosion involves several factors that complicate corrosion mechanisms due to the possible interactions (synergies, etc.) among the species present. Selective study of each individual effect, by either empirical or mechanistic modelling, is unlikely to uncover these interaction effects satisfactorily. This paper demonstrates the use of response surface methodology as a method to optimise experiments so as to capture better synergies between species and conditions. Here, the multiple effects of acetic acid, temperature, flowrate and pH are studied in the model, which was validated by experiment, prediction software and published corrosion data. In conclusion, the proposed model has shown a good agreement with the validation data, which indicates the suitability of the approach used to model carbon dioxide corrosion at pH 4-5·5. © 2012 Institute of Materials.