Knowledge graph
vs RAG.

RAG retrieves chunks of text that are similar in meaning to your question. A knowledge graph captures the explicit relationships between entities. RAG is great for "find the relevant passage"; a graph is better for "how do these things connect." The strongest digital brains often use both.

// when to use each

Similarity, or
structure?

Reach for RAG when you have a large body of documents and want the model to find and quote the most relevant bits, support docs, transcripts, a research corpus.

Reach for a knowledge graph when the value is in the connections, how clients, decisions, positions and outcomes relate, and when consistency matters (no contradicting yourself across answers).

In practice we often combine them, and we've tested how different models build these graphs in our Claude vs Fable experiment. The right mix is a tooling choice, and we pick the lowest-risk, highest-advantage option for your job.

// in plain terms

The librarian and
the detective.

Two ways to give an AI your documents. RAG is a librarian: you say a few words and it hands you the passages that mention them. Fast, and perfect when the answer sits in one place. A knowledge graph is a detective: it has already mapped who relates to what, so it can follow a trail, this client raised this concern, which ties to this decision, which changed this outcome.

The technical reason this matters: RAG matches by similarity, so it is strong at "find the relevant bit" and weak at "connect three facts that live in different places". A graph stores the connections on purpose, so multi-step questions, the ones real businesses actually ask, become possible. RAG finds the page; the graph follows the thread.

// at a glance

Side by side.

For the job of...RAGKnowledge graph
How it finds answersRetrieves text chunks similar in meaningFollows explicit relationships between entities
Best atFinding the relevant passage in lots of textReasoning over how things connect
Multi-hop questionsWeaker; the chunks don't know each otherStrong; traverse the edges
ConsistencyVaries with what gets retrievedGrounded; same relationships every time
Setup effortLighter (embed and store)More (model the entities and relationships)
Best togetherRetrieve the candidatesGround and connect them
// where graph RAG fits

The edges are
the point.

There is a hybrid people reach for called graph RAG, where semantic search is the starting point and the graph adds structure on top. The thing to watch: without edges to traverse, graph RAG loses what makes it different from plain retrieval. The edges, the relationships, are the whole point.

That is also why a graph makes a strong base for grounding. It acts as a deterministic substrate that anchors answers in your data rather than the model's intuition, which is what keeps an assistant consistent instead of contradicting itself.

// real examples

Same documents,
different jobs.

Support over 500 help articles. A customer asks how to reset a setting. RAG is enough: it finds the right article and quotes it. Impact: cheap and fast, no graph needed.

A consultant's brain across years of clients. You ask, "which past project is most like this new one, and what did we learn?" That spans many documents and relationships. This needs a graph; RAG would return scattered snippets with no thread. Impact: answers that connect your whole history instead of quoting one note.

Keeping answers consistent. If your AI must never contradict itself from one reply to the next, the graph acts as a fixed reference it checks against. Impact: a trustworthy assistant, not one that says something different each time.

And the honest default: most strong builds use both, RAG to gather candidates and the graph to connect and ground them.

// questions

Common questions.

Which is better?

Neither universally. RAG wins at retrieving relevant passages; a graph wins at reasoning over relationships. Many strong systems use both.

Can I use both together?

Yes, retrieve candidate context with RAG, then use the graph to ground relationships and keep answers consistent.

Not sure which you need?

That's exactly what we figure out together, by the outcome, not the hype. Bring it to a free session.

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