Test reactions are proposed as a quick, cheap and reliable characterisation method that can be useful for evaluating catalytic deactivation during an industrial reforming process. In this work, n-heptane reforming is evaluated as a test reaction for the characterisation of Pt-Sn/Al2O3 catalysts. The reaction has been studied using purposely prepared catalysts and the results compared to those obtained using industrial catalysts subjected to different ageing treatments. On the other hand, all catalysts have been characterised by classical methods: surface acidity has been measured by ammonia-TPD and metallic particle size has been determined by hydrogen chemisorption, and the results compared to those of test reaction. It can be concluded that the analysis of activity and selectivity in n-heptane reforming allows evaluation of the state of the catalyst, and the results are more reliable than those of classical characterisation methods. (c) 2005 Elsevier B.V. All rights reserved.