Walking is greatly significant to achieve good health, and ultimately, social sustainability. There have been numerous walkability indices developed to measure the effectiveness of walking. Limited number of these indices have been developed objectively in the context of developing countries. The current research is focused on developing a walkability index objectively, as well as finding a comparison between non-gated and gated neighborhoods, and to see how the developed walkability index is associated with walking in developing countries. The study area for this research is Karachi, Pakistan. The walkability index has been developed by utilizing entropy index for land-use-mix and Space Syntax for street connectivity, while gross housing density was considered. In order to measure the walking at neighborhood level, a questionnaire (n=1042) was used. Binary logistic regression analysis and Independent sample t-test were used for attaining results. The results show that the walkability of non-gated neighborhoods is higher than gated and there is a positive correlation between walkability and walking. The study concludes that an objectively measured walkability index can be developed in even those areas where a central database doesn't exist. Furthermore, the promulgation of walking at neighborhood level doesn't necessitate the policy of promoting the gating of neighborhoods.