A method according to an embodiment of a filter design tool is provided and includes receiving filter parameters for an analog filter through a user interface, where the filter parameters include an optimization parameter related to an application requirement of the analog filter, optimizing the filter for the optimization parameter, calculating a design output based on the optimized filter, and displaying the design output on the user interface. The method can further include receiving viewing parameters that specify the design output to be displayed. In various embodiments, the user interface includes an input area, a viewing area and a window area in one or more pages, where the input area is contiguous to the viewing area in at least one page. The filter parameters can be entered in the input area and the design output is calculated and displayed in the contiguous viewing area substantially immediately.