A topic cluster is a structure built around a single subject. At the centre sits a pillar page that covers the topic broadly but not deeply. Around it sit cluster pages, each going deep on one subtopic.
They all link to each other. When a search engine sees that network, it recognises topical authority more readily.
Why it works
- Twenty scattered posts produce twenty weak signals; a cluster produces one strong signal
- The pillar attracts external links and distributes that value to the cluster
- Users navigate within the topic, raising session depth
- Content planning gets easier: gaps become obvious
How to build one
1. Choose the topic
Take the subject at the centre of your business model. "SEO" is too broad; "e-commerce SEO" is the right scale.
2. Extract subtopics
Collect 8–15 subtopics from People Also Ask, autocomplete and customer questions. Each should map to exactly one question.
3. Write the pillar
A long page covering the whole subject, giving a few paragraphs per subtopic. Link from each section to the relevant cluster page.
4. Write the cluster pages
Each handles one subtopic thoroughly and links back to the pillar. Cluster pages may link to each other, but do not force it.
Common mistakes
- Cannibalisation. If two cluster pages target the same query, both weaken. Give every page one clear target.
- Turning the pillar into a link list. A page that is only links carries no value; it must stand on its own.
- One-way linking. If clusters link to the pillar but the pillar does not link back, the structure fails.
- Too many clusters. Fifty subtopics do not belong in one cluster; split it.
Measurement
Measure clusters in aggregate, not page by page: total impressions, average position and organic traffic across every page in the cluster. Even if the pillar underperforms alone, a rising cluster total means the structure is working.