When the architectural design is handled based on process and product, we see that many parameters come into play at the point of decision making. Especially as the design problem gets complicated, the value parameters increase so much. Producing solutions to these complex problems only with personal judgments does not yield very productive results in the accuracy of the results. Decision support systems with effective use are needed to select solution suggestions in the design process, at the point of converting personal judgments into real data. For this purpose, a structured decision support method on the fuzzy AHP approach for design evaluation is presented, and a web-based interface is introduced that increases the usability of the method in practice. The interface has been developed based on ASP.Net platform as a web-based evaluation software that allows the participation of many evaluators independent of time and space. The effectiveness and advantages of the developed software are discussed in evaluating the designs obtained in an architectural design studio environment. The software called DDSS (Design Decision Support Software) has shown that it can be applied more effectively in multi-criteria decision-making problems by eliminating the synthesis processes and providing the opportunity to reach faster results. Consequently, when the decision support method presented is used through the developed software, it is seen that more conscious and objective evaluations can be made about the designs in the decision steps in the architectural design process, which has a complex and contradictory structure intertwined with abstract concepts as characters.