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LDA SEO

Stop treating LDA as a Google ranking score. It is a statistical model for surfacing related topics, but not a signal the search engine uses.

Beginner3 min readUpdated 2026-07-27Notes by Callum Bennett

Start here

  • Ignore any tool that claims to show an LDA score for Google; the algorithm does not output one.
  • Run your topic through an LDA script or tool to find clusters of related terms, then build content around those clusters.
  • When planning a pillar page, use LDA to identify supporting articles that cover subtopics your competitors address.
  • Treat LDA as a content analysis framework, not a checklist. It helps you ask better questions about depth, not hit a number.
  • If you have thin pages, LDA can reveal what subtopics are missing compared to top-ranking content.

Plain-English take

Imagine you feed a pile of articles about "dog training" into a machine. It notices that words like "leash," "sit," and "treat" appear together often, so it groups them into one topic — call it "basic obedience." Meanwhile "barking," "growling," and "behaviourist" form another cluster labelled "aggression." That is LDA in a nutshell: it reads a collection of documents, guesses how many topics exist, and then assigns every document a mix of those topics. Every topic is a mix of words.

For SEO, the useful insight is that pages ranking well on a subject tend to cover not just the main topic but several of its related subtopics. If you write only about "dog training" without mentioning "leash training" or "crate training," your topical coverage might be thin. LDA helps you see what those subtopics are by analysing a corpus of top-ranking content. You are not optimising for a score; you are discovering the semantic neighbourhood you need to occupy.

But here is the catch: Google does not use LDA in its ranking algorithms. It uses its own systems like BERT and RankBrain for semantic understanding. LDA is a math model from the early 2000s. I treat it as a content planning compass, not a ranking lever. If a tool shows you an "LDA score," move on.

When it actually matters

LDA shines most in three scenarios. First, building a content cluster. If you are writing a pillar page on "digital cameras," run your topic through an LDA tool. The output might reveal clusters such as "mirrorless vs DSLR," "sensor size and ISO," and "budget vs professional." Each cluster becomes a supporting article. This approach saved me hours of manual research for a client in the electronics niche.

Second, auditing thin content. Run your existing pages through LDA and compare the topic distribution against the top ten results. I once had a page on "best running shoes" that ranked poorly. LDA showed I missed terms like "pronation control" and "heel drop" that every competitor included. Adding those subtopics improved the page's visibility within three months.

Third, structuring a brief for writers. Instead of asking a writer to include "relevant keywords," give them the LDA topic clusters. Tell them: the article needs to cover at least the top three clusters from the analysis. That makes the brief concrete without dictating exact word placement.

A caveat: LDA works best on moderately focused topics. For very broad terms like "health" the clusters become too many and noisy. You have to manually prune them. And never rely on LDA for [technical SEO](/technical-seo/) audits; it ignores page speed, structure, and other signals. If you are building a large site, pair it with [programmatic SEO](/programmatic-seo/) for scalability.

What I got wrong

I used to believe LDA was a direct ranking factor. I spent weeks running every new page through a third-party tool, trying to achieve an "LDA score" of 90% or higher. The tool would tell me I needed to include more of certain terms, so I stuffed them in. The result? Pages that read unnaturally and, predictably, did not rank any better. I was optimising for a metric that Google never used.

Another mistake: I assumed the model's output was fixed. LDA is probabilistic — change the number of topics you ask for, or use a different corpus, and the clusters shift. I once set the topic count too low and got a single cluster covering "camera" and "shoes" because both appeared in shopping contexts. The output was useless.

I also learned that LDA is not a substitute for understanding user intent. A topic cluster might group "cheap" and "discount" together, but if your audience wants premium products, that cluster misleads your content. Now I always verify LDA results against real search queries and competitor pages.

Finally, I ignored the fact that Google's own semantic tools are far more sophisticated. Trying to reverse-engineer a ranking through LDA is like using a fishing net to catch plankton. It catches the big clusters but misses the nuance. For duplicate content issues or thin pages, use [duplicate content](/duplicate-content/) checks or [canonical tags](/canonical-tags/) instead.

Next step

Quick answers

Is LDA used by Google in its ranking algorithm?

No. Google uses systems like RankBrain and BERT for semantic understanding. LDA is a separate statistical model from academic research. It is not part of Google's ranking signals.

Can I optimise my page for an LDA score shown by a tool?

Do not waste time. There is no official LDA score in Google's systems. The score you see is calculated by the tool based on its own corpus and parameters. Optimising for it leads to unnatural content.

How do I actually use LDA for content planning?

Collect the top 10–20 ranking pages for your target query. Run them through an LDA implementation (like a Python library or MarketMuse). Note the topic clusters and ensure your content covers the most frequent ones naturally.

Sources

Primary documentation is linked directly. Anything commercial is marked nofollow.

Notes from Callum Bennett.