What Is Six Degrees of Separation and How Does It Work on Wikipedia?

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Six degrees of separation is the idea that any two people can be connected through a short chain of acquaintances—popularly, about six steps. On Wikipedia, the same idea applies to hyperlinks: because articles link to other articles, you can often travel from any starting page to any target page through a small number of clicks. Tools such as Six Degrees of Wikipedia find these shortest hyperlinked paths for you. The concept is useful for understanding how tightly connected a large link network is, and for testing whether a surprising connection between two topics is real or just a guess.

The core idea of six degrees of separation

The phrase describes social distance: two strangers are rarely more than a handful of introductions apart. The exact number is less important than the structure behind it—each person has many contacts, and those contacts have many contacts, so the number of reachable people grows very quickly with each step. That is why long chains are usually unnecessary even in very large populations.

The same logic applies to any network where nodes connect to other nodes. Wikipedia is one such network: articles are nodes, and internal links are edges.

How Wikipedia links form a network

Every Wikipedia article can link to other articles. Treat each article as a point and each internal link as a one-way connection, and the encyclopedia becomes a large directed graph. Finding a short path between two articles means finding a sequence of links that starts at one page and ends at the other.

Two details matter when interpreting results:

  • Direction matters. A link from page A to page B does not guarantee a link from B back to A. A path found in one direction may not exist in the other.
  • Path length is counted in clicks. A path of length 3 means three link-following steps, not three articles. The starting and ending pages are the endpoints of the chain.

Short paths exist because popular or broad articles act as hubs, and many specific articles link to them. A path often runs from a narrow topic up to a general one and back down to another narrow topic.

What a shortest-path result means

A shortest-path tool returns the minimum number of links needed to get from the start page to the target page, along with the specific sequence of pages. Read the result as a claim about this particular snapshot of Wikipedia's link structure, not as a permanent fact.

Path length can vary for several reasons:

  • Links change. Editors add and remove links, so a path that exists today may not exist later.
  • The graph is directed. The shortest path from A to B can differ from the shortest path from B to A.
  • Hubs dominate. Pages with many outgoing links tend to appear in many short paths, which can make results look repetitive.

A short result does not prove the two topics are meaningfully related—only that the link structure allows a quick route between them.

Trying it with Six Degrees of Wikipedia

Six Degrees of Wikipedia is a side project that finds the shortest hyperlinked paths between any two pages on Wikipedia. Its page states that the interactive project requires JavaScript, so use a modern browser with JavaScript enabled. If scripting is blocked, the tool will not run.

A practical workflow:

  1. Open the site in a browser with JavaScript enabled.
  2. Enter a starting article and a target article.
  3. Run the search and read the returned sequence of pages.
  4. Note the number of steps and the direction of the search.

The expected result is a chain of article titles you can follow by hand.

Verifying a path manually

Because results depend on a live, changing site, confirm any path you plan to rely on:

  1. Open the starting article on Wikipedia.
  2. Find the link to the next page in the returned sequence and click it.
  3. Repeat for each step until you reach the target article.
  4. Count the clicks and compare with the reported length.

If a link is missing, the path may be outdated or the tool may have used a different link. This check also shows you which links carried the path, which is often the most interesting part.

Common sticking points

  • Nothing happens when you search. JavaScript is probably disabled or blocked; the project explicitly requires it.
  • The path looks implausible. Follow it manually—short paths often pass through broad hub articles that seem unrelated to either endpoint.
  • Results differ between runs or directions. Link structures change and are directional, so treat any single result as one valid route rather than the only one.

Used this way, six degrees of separation on Wikipedia is less a fixed rule than a quick way to see how short the routes through a huge link network can be—and a prompt to check the route yourself.