Graph Connectivity Calculator

Check whether a graph is connected and list the vertices reachable from a starting node. This educational calculator shows the result, explains the rule, and gives step-by-step reasoning.

Computer ScienceDiscrete MathGraph Theory

Calculator

Nodes
Edges
Start node
Please enter valid graph or number inputs.

What this calculator teaches

Check whether a graph is connected and list the vertices reachable from a starting node.

Graph theory and algorithm mathematics are core parts of discrete math and computer science. They help explain networks, dependency graphs, search, optimization, data structures, and route planning.

Formula & Symbols

ConceptFormula or rule
Connected graphEvery vertex is reachable from every other vertex
ReachabilityUse BFS or DFS from a starting vertex

Worked Example

Example
Try the default values
  • If E has no edge connected to the rest of the graph, the graph is not connected.
  • Click Calculate to see the result and the algorithm steps.
  • Change one edge, node, or weight and compare how the output changes.
The calculator output explains both the answer and the method.

When to use it

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Discrete math learning
Practice the graph and algorithm idea with visible steps.
šŸ’»
Computer science
Use the result to understand algorithms, data structures, and networks.
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Problem checking
Check homework-style examples and compare with manual work.

Common mistakes

āš ļø
Mixing directed and undirected edges

Use arrows like A>B when direction matters. Use A-B when the edge should work both ways.

āš ļø
Forgetting edge weights

Weighted algorithms need entries such as A-B:5. If no weight is supplied, the calculator treats the edge weight as 1.

āš ļø
Using very large brute-force inputs

Some graph problems grow quickly. Hamiltonian path and similar searches are meant for small educational graphs.

FAQ

Is this a graphing calculator for coordinate graphs?āŒ„
No. This page focuses on graph theory, where a graph means vertices connected by edges.
How should I enter edges?āŒ„
Use comma-separated edges like A-B, B-C, or weighted edges like A-B:4. Directed edges can be written as A>B or A>B:4.
Are the steps exact algorithms?āŒ„
The calculators use standard educational versions of the algorithms and show the main reasoning steps so students can follow the method.

Related calculators

Use related discrete math and algorithm calculators to compare graph representations, paths, sets, and recurrence behavior.

Formula Explorer connections

Interpretation: This formula or algorithm measures graph structure, traversal, reachability, path cost or network connectivity. Assumption: Specify whether the graph is directed or weighted and whether negative edges, cycles or disconnected components are allowed by the chosen algorithm.

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