The main idea for practicing research towards security is to maintain usability of the software as well. This can be achieved by making less complex and high secure software. Though considerable efforts have been made in this context by the developers and security experts, the standard of usable-security is not the same as it should be. Therefore, it is important to research more on the most conversant mechanisms for assessing and increasing the usable-security of software. The quantitative evaluation of usability and security is an important part in increasing the level of secure software. This paper, in particular, is intended to estimate the usable-security of software and achieve the objective of developing software with optimum security while retaining its usability. The decision-makers often find it difficult to integrate security and usability. Hence this paper approaches the integration of usability and security with its contributing attributes. Also, in this league, the present research study suggests a novel technique which is the hybrid of Analytic Hierarchy Process (AHP), Hesitant Fuzzy (HF) sets, and Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) to significantly assess the usability along with security. To test the usefulness of the proposed approach hybrid HF-AHP-TOPSIS technique, the researchers applied it onto software developed for Babasaheb Bhimrao Ambedkar University in India. Furthermore, the procedural sensitivity was also achieved by using the various versions of the method. The findings of the usability along with security assessment insist that this inventive hybrid procedure would be the most conversant mechanism for determining the usable-security of software. Further these findings will be helpful in managing security without affecting the usability for end user. INDEX TERMS Software development life cycle, software security, usable-security, hesitant-fuzzy-AHP, hesitant-fuzzy-TOPSIS.