Engineering practise heavily relies on the development and use of mathematical models. In this article a number of appropriate metrics have been selected to provide an insight in the validation of models and also to obtain a 'figure of merit' for any given model. The latter exercise enables categorisation of models with respect to their performance if more than one model is available, or developed, for any given task. A Microsoft Excel/Visual Basic for Applications software has been expressly developed for the latter task that enables automation of the model validation work. This software product is provided on this research team's website. The reader may download this shareware-software as an open access tool. (C) 2011 Elsevier B.V. All rights reserved.