Cluster Map

A cluster map is an interactive mapping technique that dynamically groups overlapping or closely spaced point markers into consolidated cluster symbols. Each cluster is typically rendered as a circle whose size or label indicates how many individual points it contains. As the user zooms in, clusters break apart to reveal their constituent markers, and zooming out re-aggregates them. This approach solves the common problem of marker overload, where thousands of overlapping pins render a map unreadable. Clustering algorithms used in web maps include grid-based clustering, distance-based (DBSCANDBSCANDBSCAN (Density-Based Spatial Clustering of Applications with Noise) is an unsupervised clustering algorithm that gro...-style) grouping, and hierarchical approaches like Supercluster (used in MapboxMapboxMapbox is a robust platform that equips developers with tools to create highly customizable, interactive maps for web... and MapLibre). The algorithm parameters—cluster radius, minimum points, and maximum zoom—control how aggressively markers are grouped. Some implementations color-code clusters by category composition or animate transitions as clusters split and merge during zoom. Cluster maps are widely used for store locators, event listings, real-estate platforms, field observation databases, and IoT sensor networks. LeafletLeafletLeaflet is a lightweight, mobile-friendly JavaScript library for building interactive mapping applications. Known for....markercluster, Mapbox GL JS’s built-in clustering, Google Maps MarkerClusterer, and OpenLayersOpenLayersOpenLayers is a mature, open-source JavaScript library for building interactive web maps that support a wide range of... cluster source all provide ready-made implementations. Best practices include displaying a count label inside each cluster, using a click-to-zoom interaction so users can explore dense areas, and optionally providing a spider or spiral layout to separate co-located markers at maximum zoom.