Gephi is an open source software for exploring and manipulating networks. It uses a 3D render engine to display large networks in real-time and to speed up the exploration. A flexible and multi-task architecture allows for working with complex data sets and produces valuable visual results. The software provides easy and broad access to network data and allows for spatializing, filtering, navigating, manipulating and clustering. It also highlights dynamic features of network visualization. The visualization of large graphs has been developed for many years in successful projects. Visualizations are useful to leverage the perceptual abilities of humans to find features in network structure and data. However, this process is inherently difficult and requires exploration strategy. Network exploration tools must be technically accurate and visually attractive, and must head toward real-time visualizations and analysis to improve the user's exploratory process. Interactive techniques have successfully guided domain experts through the complex exploration of large networks. Gephi is an open source network exploration and manipulation software. It can import, visualize, spatialize, filter, manipulate and export all types of networks. The visualization module uses a special 3D render engine to render graphs in real-time. This technique uses the computer graphic card, as video games do, and leaves the CPU free for other computing. It can deal with large networks and takes advantage of multi-core processors. Node design can be personalized, and highly configurable layout algorithms can be run in real-time on the graph window. Several algorithms can be run in the same time, in separate workspaces without blocking the user interface. The text module can show labels on the visualization window from any data attribute associated to nodes. A special algorithm named Label Adjust can be run to avoid label overlapping. The user interface is structured into Workspaces, where separate work can be done, and a powerful plugin system is currently developed. Great attention has been taken to the extensibility of the software. An algorithm, filter or tool can be easily added to the program, with little programming experience. Sets of nodes or edges can be obtained manually or by using the filter system. Filters can select nodes or edges with thresholds, range and other properties. In practice filter boxes are chained, each box takes in input the output of the upper box. Thus, it is easy to divide a bi-partite network or to get the nodes that have an in-degree superior to 5 and the property "type" set to "1". Gephi is available at http://gephi.org.Gephi is an open source software for exploring and manipulating networks. It uses a 3D render engine to display large networks in real-time and to speed up the exploration. A flexible and multi-task architecture allows for working with complex data sets and produces valuable visual results. The software provides easy and broad access to network data and allows for spatializing, filtering, navigating, manipulating and clustering. It also highlights dynamic features of network visualization. The visualization of large graphs has been developed for many years in successful projects. Visualizations are useful to leverage the perceptual abilities of humans to find features in network structure and data. However, this process is inherently difficult and requires exploration strategy. Network exploration tools must be technically accurate and visually attractive, and must head toward real-time visualizations and analysis to improve the user's exploratory process. Interactive techniques have successfully guided domain experts through the complex exploration of large networks. Gephi is an open source network exploration and manipulation software. It can import, visualize, spatialize, filter, manipulate and export all types of networks. The visualization module uses a special 3D render engine to render graphs in real-time. This technique uses the computer graphic card, as video games do, and leaves the CPU free for other computing. It can deal with large networks and takes advantage of multi-core processors. Node design can be personalized, and highly configurable layout algorithms can be run in real-time on the graph window. Several algorithms can be run in the same time, in separate workspaces without blocking the user interface. The text module can show labels on the visualization window from any data attribute associated to nodes. A special algorithm named Label Adjust can be run to avoid label overlapping. The user interface is structured into Workspaces, where separate work can be done, and a powerful plugin system is currently developed. Great attention has been taken to the extensibility of the software. An algorithm, filter or tool can be easily added to the program, with little programming experience. Sets of nodes or edges can be obtained manually or by using the filter system. Filters can select nodes or edges with thresholds, range and other properties. In practice filter boxes are chained, each box takes in input the output of the upper box. Thus, it is easy to divide a bi-partite network or to get the nodes that have an in-degree superior to 5 and the property "type" set to "1". Gephi is available at http://gephi.org.