How to Find Related (“LSI”) Keywords for Your Content
Related keywords help you cover a topic fully, and help one article rank for many searches. Here's how to find them, and the truth about 'LSI keywords'.
Key takeaways
- Google doesn't use LSI (latent semantic indexing); the term is a misnomer for related terms and subtopics.
- Covering related subtopics helps one page rank for many related searches.
- Find related terms in People also ask, related searches, competitor headings and Search Console.
- Use them where they make the content more complete, not as a list to insert.
“LSI keywords” is a common SEO term for words and phrases related to your main topic. The name comes from latent semantic indexing, an old information-retrieval technique. Google has said it doesn’t use LSI. But the underlying idea, that thorough pages naturally include related concepts, is sound.
A better description: related keywords or semantic keywords: the subtopics, entities and questions someone expects a complete page on your topic to cover.
Why related keywords matter
A page about “Meta ads audit” that also covers pixel setup, Conversions API, event match quality, frequency, creative fatigue and Advantage+ campaigns:
- Is genuinely more useful
- Signals to Google that it covers the topic in depth
- Can rank for dozens of related searches, not just one
Where to find related keywords (free)
- People also ask: questions to answer as subheadings or FAQs
- Related searches at the bottom of Google’s results
- Autocomplete variations
- Competitor headings: the H2s on the top-ranking pages show subtopics Google associates with the query
- Search Console: queries your page already appears for that it doesn’t yet answer well
- Google Keyword Planner: related ideas grouped by theme
- Glossaries and documentation: platform terms (see our glossary)
How to use them
- Map subtopics to sections. Each important related concept may deserve its own H2 or H3.
- Answer the questions directly, in a sentence or two, under a clear heading.
- Use the terms people use, including synonyms (“PPC,” “paid search,” “Google Ads”).
- Link to deeper pages for subtopics that deserve their own article (internal linking).
What not to do
- Don’t paste a list of terms into the page
- Don’t force awkward phrases or exact repetitions (keyword density isn’t a thing)
- Don’t stretch an article with loosely related tangents
A quick check
Compare your outline with the top three results. Which important subtopics do they all cover that you don’t? Which useful points could you add that none of them include, such as first-hand experience, local detail or real examples? That second list is how you beat them.