What is a filter in UX design?
A filter is a UI mechanism that allows users to narrow a set of content or results by applying one or more criteria. Filters are used in product catalogs, search results, data tables, content libraries, and any interface where users need to find specific items within a large collection. Effective filters reduce the cognitive effort of finding relevant content by hiding irrelevant items rather than requiring users to scan everything to identify what matches their needs.
What are the types of filter patterns in UX design?
Faceted filters present multiple independent filter dimensions simultaneously, typically in a sidebar or filter panel. Users can apply filters from any dimension in any order and see results update accordingly. This pattern works well for product catalogs and content libraries with multiple meaningful attributes. Sequential filters guide users through filter criteria in a defined order, common in booking flows where selecting dates before selecting availability makes sense. Inline filters embed filter controls directly within the result list, typically as chips or tags that can be toggled on and off.
How should filters communicate their state to users?
Applied filters must be clearly visible so users know which criteria are currently active. Show active filters as removable chips or tags near the results, not only within the filter panel. Show the number of results that match the current filter combination so users understand the impact of their selections. When no results match the applied filters, provide a clear empty state that explains what happened and offers a path forward such as clearing filters or adjusting criteria. Update results in real time or with a clear apply action, but be consistent within the interface.