Int. J. of Web Engineering and Technology, Vol. 1, No. 1, 2003 5 Copyright © 2003 Inderscience Enterprises Ltd. Measuring the functional size of web applications Silvia Abrahão and Oscar Pastor Department of Information Systems and Computation, Valencia University of Technology, Camino de Vera s/n, 46071 Valencia, Spain Fax: 34-96-387-7359 E-mail: sabrahao@dsic.upv.es E-mail: opastor@dsic.upv.es Abstract: Today, more and more Web sites and Applications (WebApps) are becoming mission-critical systems. Measures of functional size are a prerequisite to successful quantitative management of software projects. However, the nature of the web has recently imposed new and challenging characteristics, which are not supported by the existing estimation metric and models. In order to avoid the Web crisis, urge the use of web engineering approaches for developing and estimating web projects in a systematic way. To achieve this goal, we present a novel size metric for accurately measuring the functional size of web applications early in the development life cycle. The main contribution of this work is the introduction of a measurement process that is embedded in the conceptual modelling phase of a model-driven approach for developing web applications. The results obtained from our experiments with this approach are outlined in this work. Keywords: web engineering; conceptual modelling; object-oriented; web metrics; function points; functional size measurement. Reference to this paper should be made as follows: Abrahão, S. and Pastor, O. (2003) ‘Measuring the functional size of web applications’, International Journal of Web Engineering Technology, Vol. 1, No. 1, pp. 5–16. Biographical Notes: Silvia Abrahão is an Assistant Professor in the Department of computation and information systems at the Valencia University of Technology in Spain. She received a BS in computer science from FPTE in Brazil. She is currently a PhD candidate in computer science at the Valencia University of Technology. Her research interests include web engineering, object-oriented conceptual modelling, and software quality. Oscar Pastor is currently the Head of the Department of computation and information systems, Valencia University of Technology (VUT) in Spain, and the leader of the OO-Method Research Group in the same department. He received his PhD degree from the VUT in 1992, after a research stay in HP Labs, Bristol, UK. He is Professor of Software Engineering at the VUT. His research activities have involved conceptual modelling, requirements engineering, information systems, web-oriented software technology and model-based code generation. He has received numerous research grants from public institutions and private industry and has devoted considerable effort to the issues of technology transfer from academia to industry.