This paper introduces a methodology to improve the accessibility of websites with the use of free so-called automatic tools. The methodology has three iterative phases, namely assessing a website against accessibility guidelines, user testing and creating in-house ‘guidelines’ to prevent similar mistakes in future versions of the system. Aspects of accessibility addressed include the use of colour, accessibility guidelines and priorities, readability or comprehensibility, and screen reader simulators. We recommend free tools for each of these accessibility aspects and discuss the process that should be followed when evaluating a website. Categories and Subject Descriptors H.5.2 [User Interfaces]: Evaluation/methodology, Screen design, User-centered design; H.5.3 [Group and Organization Interfaces]: Web-based interaction. General Terms Design, Human Factors. Keywords Automatic accessibility evaluation, disabilities, usability evaluation.