Graph Theory Visualizer

PyNode allows you to create, animate and display graphs with a simple Python interface, all within your browser.
Try the examples below, or write your own!

Note: You can now use AlgorithmX to create even better network visualizations!













  • graph.add_node(node) - Adds a node to the graph.

  • graph.add_node(id=None, value=id) - Creates a Node(id, value) and adds it to the graph.

  • graph.remove_node(node) - Removes a node from the graph.

  • graph.node(id) - Returns a node in the graph by its id.

  • graph.nodes() - Returns a list of all nodes in the graph.


  • graph.add_edge(edge) - Adds an edge to the graph.

  • graph.add_edge(source, target, weight=None, directed=False) - Creates an Edge(source, target, weight, directed) and adds it to the graph.

  • graph.remove_edge(edge) - Removes an edge from the graph.

  • graph.remove_edge(node1, node2, directed=False) - Removes edge(s) between node1 and node2. If directed is set, only edges beginning at node1 will be removed.


  • graph.has_node(node) - Checks whether a node has been added to the graph.

  • graph.has_edge(edge) - Checks whether an edge has been added to the graph.

  • graph.adjacent(node1, node2, directed=False) - Checks whether an edge exists between node1 and node2. If directed is set, the edge must begin at node1.

  • graph.edges_between(node1, node2, directed=False) - Returns a list of all edges between node1 and node2. If directed is set, only edges beginning at node1 will be included.


  • graph.set_directed(directed=True) - Sets whether all edges in the graph are directed.

  • graph.adjacency_matrix() - Creates and returns an adjacency matrix (2-dimensional dictionary, using node id values as keys) for the graph.

  • graph.add_all(elements) - Adds a list of Node and/or Edge elements to the graph.

  • graph.remove_all(elements) - Removes a list of Node and/or Edge elements from the graph.

  • graph.random(order, size, connected=True, multigraph=False, initial_id=0) - Returns a list of randomly connected nodes and edges, with order specifying the amount of nodes and size specifying the amount of edges. If connected is set, a path will exist between any pair of nodes (unless the amount of edges makes this impossible). If multigraph is set, a pair of nodes may be connected by multiple edges. Nodes are assigned incremental id values starting at initial_id.

  • graph.order(), graph.size() - Returns the number of nodes/edges in the graph.

  • graph.clear() - Deletes all nodes and edges from the graph.

Note: All functions containing node parameters accept either a Node instance or node id value.



  • Node(id=None, value=id) - Creates a node with the specified id and value. Assigns a unique id integer if the specified id is None.

  • - Returns the id of the node.

  • node.set_value(), node.value() - Sets/gets the value of the node.

  • node.incident_edges(), node.incoming_edges(), node.outgoing_edges() - Returns a list of the node's incident/incoming/outgoing edges.

  • node.adjacent_nodes(), node.predecessor_nodes(), node.successor_nodes() - Returns a list of the node's adjacent/predecessor/successor nodes.

  •, node.indegree(), node.outdegree() - Returns the node's degree/indegree/ outdegree.

  • node.set_attribute(name, value), node.attribute(name) - Sets/gets custom attributes for the node.

  • node.set_priority(value), node.priority(name) - Sets/gets a priority value used for comparison.


  • node.set_position(x, y, relative=False) - Sets the static position of the node. x and y are pixel coordinates, with (0, 0) being the top-left corner of the output window (the standard size of the window is 500x400). If relative is set, x and y should instead be values between 0.0 and 1.0, specifying the node's position as a percentage of the window size.

  • node.position() - Returns a tuple with the (x, y) coordinates of the node. Should be used in asynchronous function calls.

  • node.set_label(value, label_id=0), node.label(label_id) - Sets/gets the value of additional labels for the node (Use label_id=0 for the top-right label and label_id=1 for the top left-label).

  • node.set_size(size=12), node.size() - Sets/gets the radius of the node.

  • node.set_color(color=Color.DARK_GREY), node.color() - Sets/gets the color of the node.

  • node.set_value_style(size=13, color=Color.WHITE, outline=None) - Sets the appearance of the node's value text (if no outline is specified, the node's background color will be used for the outline).

  • node.set_label_style(size=10, color=Color.GREY, outline=None, lable_id=None) - Sets the appearance of the node's label text (if no lable_id is specified, both labels will be affected).

  • node.highlight(color=node.color(), size=node.size()*1.5) - Performs a highlight animation by temporarily changing the size and color of the node.



  • Edge(source, target, weight=None, directed=False) - Creates an edge between the specified source and target nodes, with optional weight and directed properties.

  • edge.source(), - Returns the edge's source/target nodes.

  • edge.set_weight(weight=None), edge.weight() - Sets/gets the weight of the edge.

  • edge.set_directed(directed=True), edge.directed() - Sets/gets whether the edge is directed.

  • edge.other_node(node) - Returns a node connected by the edge, other than the node specified.

  • edge.set_attribute(name, value), edge.attribute(name) - Sets/gets custom attributes for the edge.

  • edge.set_priority(value), edge.priority(name) - Sets/gets a priority value used for comparison.


  • edge.set_width(width=2), edge.width() - Sets/gets the width of the edge.

  • edge.set_color(color=Color.LIGHT_GREY), edge.color() - Sets/gets the color of the edge.

  • edge.set_weight_style(size=10, color=Color.GREY, outline=None) - Sets the appearance of the edge's weight text.

  • edge.highlight(color=edge.color(), width=edge.width()*2) - Performs a highlight animation by temporarily changing the width and color of the edge.

  • edge.traverse(initial_node=edge.source(), color=Color.RED, keep_path=True) - Performs a traversal animation on the edge, beginning at initial_node and using the specified color. If keep_path is set, the edge will remain colored.



  • Color(red, green, blue) - Custom color for use in node and edge animations, using 0-255 values for each component.

  • Color.RED, Color.GREEN, Color.BLUE, Color.YELLOW, Color.WHITE, Color.LIGHT_GREY, Color.GREY, Color.DARK_GREY, Color.BLACK, Color.TRANSPARENT - Predefined colors for use in node and edge animations.

  • pause(time) - Delays the next visual event for the specified number of milliseconds (note that this does not pause code execution).

  • delay(func, time, args=[], repeat=False) - Executes a function after the specified number of milliseconds, with the optional args list of parameters. If repeat is set, the function will execute continuously until the delay is cancelled. Returns a delay_id integer referencing the delay.

  • cancel_delay(delay_id) - Cancels a scheduled delay event.

  • register_click_listener(func) - Registers a function which will be called whenever a node is clicked. The function must include a node parameter (e.g. def on_click(node)), which will receive the instance of the clicked node.



Download the offline version of PyNode below.




Once downloaded, unzip the archive and run



PyNode was designed and created by Alex Socha, using the following technologies: