Responsive web designing is booming in the world due to its practical nature that serves and responds according to different user. The use of smart phones and tablets has compelled IT industry to come up with an idea that support these devices with different operating systems. Responsive website is design in such a way that it’s content, images, and layout coordinate themselves in display best in response to the device that is being use to view the website Before analyzing the factor that affects cost, let throw some insight on why optimizing users experience for different display types is important. The reasons is 1. Give consistent user experience no matter which device accesses the site's content. 2. Create a single coded website for all online customer experience. 3. Reduce maintenance 4. Offer better marketing visibility Designing a responsive website is currently considered as a best practice, but there are many factors that can impact the cost of responsive design development. These are: 1. Functionality: The type of functionality you want including contact forms, log-in forms, drop down or navigation menus. And any other dynamic enhancements . 2. Breakpoints: More breakpoints mean more your responsive design site will theoretically cost. 3. Content: Content requirement of website sometime increase development time. 4. Customization: If you have basic requirements then you can use templates as other uses but customers typically want a design that is customized to their brand. Customize website according to you requirements doesn’t always affect the cost of a responsive design but often does. 5. Performance: Optimizing website performance will cost more as more breakpoints are required in the controlling the cost of website performance. If you are looking for getting responsive then consult with user experience design professionals to improve your website experience for better conversion.