Glossary
What is a topic cluster?
A pillar page on a broad subject plus linked pages that each go deep on one subtopic, so a site covers the topic fully.
Definition
A topic cluster is a group of web pages about one broad subject: a pillar page that covers the topic as a whole, plus cluster pages that each go deep on one subtopic, all linked to each other. The structure helps readers find related answers and makes it clear to search engines what a site covers in depth.
How a topic cluster works
You pick a broad topic your buyers care about and map the questions they ask around it. The pillar page gives a complete overview and links out to a cluster page for each important subtopic. Each cluster page links back to the pillar and, where it helps the reader, to its sibling pages.
Instead of dozens of unrelated posts, you end up with an organized body of work on a subject. That makes it easier for visitors to keep reading, and easier for search engines and AI assistants to see that your site is a strong source on the topic.
Pillar page vs cluster page
- Pillar page. Targets the broad, high-level query, such as "cold email." Covers every major part of the topic at a summary level, then points readers to the details.
- Cluster page. Targets one specific question, such as "how many follow-up emails to send." Answers it fully and links back to the pillar.
Each cluster page should match the search intent of its own query.
An example
Say you run a payroll service for restaurants. Your pillar page is "Restaurant payroll: the complete guide." Cluster pages cover tip reporting, paying staff who work at two locations, overtime rules for kitchen staff, and choosing payroll software. Every cluster page links to the guide, and the guide links to each one. Over time, you add new cluster pages as customers ask new questions.
Common mistakes
- Pillar pages that try to rank for everything. Summarize, then link out. Don't stuff every detail into one page.
- Cluster pages that overlap. Two pages answering the same question compete with each other. Merge them.
- Missing links. Without links between pillar and cluster pages, it's just a pile of posts.
- Topics nobody searches. Build clusters around questions buyers actually ask.
How Siela AI uses it
Siela's SEO Blog Writer turns a keyword into a researched draft, which can serve as a cluster page in a larger topic plan.
Questions
How many pages should a topic cluster have?
There's no fixed number. A cluster needs enough pages to cover the main questions buyers ask about the topic, which might be five or thirty. Start with the most important subtopics, publish them well, and add more as you learn what people search for.
Do topic clusters still matter with AI search?
The underlying idea does. AI assistants and search engines both favor sources that answer a topic clearly and thoroughly. An organized set of linked pages that each answer one question well is easier to find, understand and cite than scattered, overlapping posts.
Less jargon, more conversations.
Siela AI finds people with a fresh reason to talk, reaches them on LinkedIn, X and email from your own accounts, and keeps your social going.