By Mehdi HassanWhat is topical authority, and why is there no magic number?
Topical authority is the trust a search engine or AI system gives a site because it has covered a subject completely and well, not just once. When your site answers every important question in a subtopic, engines learn to return to you for that subject, including for queries you never targeted directly.
The trouble with "you need 30 articles" advice is that subtopics differ wildly in size. "SOC 2 for startups" might have eight real questions behind it; "B2B content strategy" has dozens. A fixed number either leaves gaps in big topics or forces filler into small ones, and filler is exactly what Google's scaled content abuse policy targets. We cover how topics fit into a wider plan in our B2B content strategy guide.
So the right question isn't "how many articles". It's "how many distinct questions does this subtopic contain, and which of them deserve their own page". The rest of this article is a method for answering that.
How do you size a subtopic for topical authority?
You size a subtopic by listing every question a buyer asks about it, grouping questions that share one answer, and giving each group that needs more than a few paragraphs its own page. The count that comes out is your target for that subtopic.
Name the subtopic narrowly
Pick something a buyer would search as one theme, such as "Webflow migrations", not "websites". If you can't describe it in four words, it's probably two subtopics.
Collect every question
Pull questions from sales calls, support tickets, People Also Ask, Search Console queries and a few ChatGPT prompts. Write them as the buyer would say them.
Group by answer, not by keyword
Two questions belong together if the same page would answer both well. "Webflow migration cost" and "how much to move to Webflow" are one page; "Webflow migration cost" and "Webflow migration checklist" are two.
Decide page or section
A group gets its own page if its answer needs a table, steps or more than about 300 words. Smaller groups become an H2 inside a related page or an FAQ answer.
Add the hub
Every subtopic gets one hub page that answers the broad question and links to each spoke. The hub is the page you want cited for the head term.
Map each page to a next step
Note which offer or money page each article leads to. A page with no logical next step is a sign it belongs in a different subtopic, or nowhere.
Run this on a real subtopic and you get a number that fits it: small for a narrow theme, much larger for a broad one. That number is an output of the method, not a target to hit.
How do you build topical authority without spreading too thin?
Build topical authority by finishing a small number of subtopics completely before starting new ones. Three subtopics covered end to end beat ten subtopics with two posts each, because engines judge coverage per subject, not per site.
A practical order for a startup is: first the subtopic closest to your product and pricing, then the one buyers research just before they compare vendors, then the problem-awareness subtopic at the top of the funnel. Each finished subtopic also gives you a reusable topic cluster and pillar page structure for the next one.
This also keeps the work honest. Finishing a subtopic means writing the hard pages too: pricing, comparisons and objections, which are the ones that convert.
Which pages count toward topical authority?
Every indexable page on the subject counts, not only blog posts. Product pages, pricing, comparison pages, case studies, docs and glossary entries all tell an engine what you know and what you sell.
That matters more in AI search. TripleDart's Q1 2026 study of 28 B2B SaaS companies found homepages earned 31.9% of LLM citations and 81.7% of AI-attributed leads, while general blog posts drew 12,000 sessions and zero leads. Pricing comparisons and long-form deep dives were the only blog formats that converted. That's a strong argument for counting money pages as the core of a topic, with articles around them, and for reading our guide to bottom-of-funnel SEO for SaaS before you plan another top-of-funnel post.
Page type | Role in the topic | Build when |
|---|---|---|
Product or service page | Defines what you sell | First |
Pricing and comparison pages | Answers the decision questions | First |
Subtopic hub | Owns the broad question | Before the spokes |
How-to and guide spokes | Answer each distinct question | After the hub |
Glossary entries | Define terms and link inward | Once spokes exist |
Case studies | Prove the claims | Whenever you have one |
How much content depth does each page need?
Each page needs enough depth to fully answer its question and the next two questions a reader will have, and no more. Content depth is about completeness for one intent, not word count.
A useful test: after reading the page, would the buyer need to open another tab to act? If yes, the page is shallow. If they'd skim past whole sections that answer a different question, the page is bloated and should be split. Answer the question in the first two sentences, then give the specifics: steps, numbers, trade-offs and a verdict. A good content brief forces these decisions before anyone writes.
Hypothetical example: sizing a "SOC 2 for startups" subtopic
For example, suppose a compliance startup lists 31 buyer questions about SOC 2. Grouping by answer gives 11 groups. Four are small ("is SOC 2 a law?", "who issues a SOC 2 report?") and become FAQ answers on the hub. Seven need tables or steps: cost, timeline, Type 1 vs Type 2, the readiness checklist, choosing an auditor, SOC 2 vs ISO 27001, and what to show customers. That's one hub and seven spokes, plus the existing pricing and product pages.
The team publishes those eight pages before writing anything about the next subtopic. The number 8 came from the questions, not from a target.
How do internal links turn articles into a topic?
Internal links are what make separate articles read as one body of knowledge. Without them, ten posts on one subject look like ten unrelated pages.
- Hub to every spoke, in a visible list or table near the relevant section, not buried in a footer.
- Every spoke back to the hub, early in the page, with descriptive anchor text.
- Spokes to their siblings where the reader's next question is answered elsewhere.
- Spokes to the money page that matches their intent, so authority flows toward what you sell.
Audit this whenever you publish a new spoke. The most common gap we see is new posts that link out to older ones while nothing links in, which leaves them orphaned. An on-page SEO audit catches it quickly.
How do you know when a subtopic is complete?
A subtopic is complete when every question on your list has a home, each home links to the hub, and new questions from sales calls keep landing on pages you already have. At that point, new articles in the cluster add little, and refreshing existing pages adds more.
Watch three signals: Search Console shows your hub and spokes earning impressions for queries you never wrote for; prompt checks in ChatGPT and Perplexity start citing your pages for the subject; and sales stops hearing questions your site doesn't answer. When all three show up, start the next subtopic and put the finished one on a refresh schedule.
