Content gap analysis for SEO is the process of finding the topics your audience searches for, and needs answered, that your site does not cover or covers worse than the pages that win. What it produces is not a spreadsheet but a short list of decisions: write a new page, add a section to an existing one, rewrite a page that misses what people want, or leave the gap alone.
This guide sets out how to run one, step by step, for classic search results and for AI answers. It draws mainly on four published sources, each linked where it is used and each read on 13 October 2026:
- Ahrefs' guide to content gap analysis by Despina Gavoyannis, updated 17 February 2025
- Semrush's step-by-step guide by Vlado Pavlik, dated 23 June 2026
- Google's guidance on helpful, people-first content
- Google's Search Console help page for the Performance report
Ahrefs and Semrush both sell the gap tools their guides describe, and TopCited builds AI-answer monitoring and content optimization. So we say who said what, and we quote where the wording matters.
Key definitions
| Term | What it means |
|---|---|
| Content gap | A topic or question your audience needs answered that your site does not cover, or covers worse than the pages that rank or get cited for it. |
| Content gap analysis | Comparing what your audience wants, and what competing pages cover, with what your content actually answers, then deciding what to do about each difference. |
| Keyword gap | The keywords competitors rank for and you do not. One input to a content gap analysis, not the whole of it. |
| Domain-level gap | Ahrefs' term for a topic competitors have content about and you do not. |
| Page-level gap | Ahrefs' term for a topic you and a competitor both cover, where their page ranks for more keywords than yours. |
| Missing and Untapped | Two filters in Semrush's Keyword Gap tool. Missing shows keywords all the competitors you entered rank for and you do not. Untapped shows keywords at least one of them ranks for and you do not. |
The four kinds of content gap
Semrush's guide defines a content gap analysis as "the practice of finding relevant topics you haven't covered or could cover better to improve your online visibility and meet your audience's wants", and sorts the gaps it finds into four types. Each needs a different fix, which is why it is worth naming the type before acting.
| Gap type | What it means (Semrush's definition) | How you usually find it | Usual fix |
|---|---|---|---|
| Topic gap | Your audience cares about a topic, but your site doesn't cover it yet | Competitor keyword gap reports, and audience research such as sales calls and support tickets | A new page, if the topic belongs on your site |
| Intent gap | You have content that covers the topic, but it doesn't match what the audience wants | Reading the pages that rank, and the AI answers, for the query you care about | Rewrite or restructure the existing page around what the searcher wants |
| Quality gap | You have content that covers the topic, but it's thin, outdated, unclear, or otherwise low in quality | Pages losing traffic, and competitor pages ranking for more keywords on the same topic | Update and expand the existing page |
| Originality gap | You have content that covers the topic, but it mostly repeats what competing pages already say | Comparing your page with the top results and the pages AI answers cite | Add something only you have: first-party data, first-hand experience, specific examples |
Ahrefs' guide uses a simpler split that covers the same ground. Domain-level gaps "occur when competitors have content about topics you don't". Page-level gaps occur when you and a competitor both have a page on a topic but theirs ranks for more keywords, and "in most cases, this happens because they have more in-depth content than you do."
Why a keyword gap report is not a content gap analysis
The most common shortcut is to export a competitor keyword gap and call it the analysis. Both guides warn against stopping there, for different reasons.
- It only sees what people type into a search engine. Semrush points out that many topics your audience researches "never get typed into Google or asked about in ChatGPT". They come up in "sales calls, support tickets, product reviews, customer interviews, and community discussions" instead. Its conclusion: "A better, more modern content gap analysis considers keyword and prompt data to be inputs rather than the entire strategy."
- It cannot judge relevance. Ahrefs' own walkthrough shows a gap report flagging a Moz page that lists the top 500 most popular websites. It ranks for 120 keywords the Ahrefs site does not, with 2,187 estimated monthly search visits. Then the author expands the row and finds that "it looks like they aren't very relevant to our business", and moves on. A gap with traffic and no fit is not a gap worth filling.
- It does not see AI answers. A Semrush study by Rachel Handley, dated 21 July 2025, reports that the pages ChatGPT search cites "rank in traditional organic search positions 21+ for related queries almost 90% of the time, according to our data." That is Semrush's data, from a company that sells AI visibility tracking. Its guide draws the consequence that "a page can perform well in organic search and still be missing from AI-generated answers."
How to do a content gap analysis for SEO, step by step
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Define the audience and the topics you need to own. Start from what your site is for, not from a tool. Google's people-first questions include: "Do you have an existing or intended audience for your business or site that would find the content useful if they came directly to you?" A gap outside that audience is somebody else's gap.
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Choose competitors by audience, not by brand. The sites that rank for your topics may be publishers, review sites or documentation, not the companies you sell against. Ahrefs' tool offers suggestions if you do not know your competitors. Check each one, because a site that shares your keywords but not your customers fills the report with topics like the Moz example above.
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Run a competitor keyword gap. The two guides describe their own tools:
- Ahrefs: set the Competitive Analysis tool to "keywords", enter your domain and 1-3 competing domains, click "Show keyword opportunities", and switch on "main positions only" to drop rankings in image packs, sitelinks and carousels.
- Semrush: in Keyword Gap, add your domain and up to four competitors and click "Compare". Missing lists the keywords all of them rank for and you do not. Untapped lists the ones at least one ranks for.
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Cut the list down before you read it. Ahrefs suggests:
- excluding competitors' brand names, with partial matches to catch misspellings
- excluding topics irrelevant to your site
- when checking several competitors, requiring at least two of them in the top 10
- a minimum monthly search volume of 20
- a maximum Keyword Difficulty of 30 to surface easier wins
Above 100,000 keywords, it warns, the export will probably break its Google Sheets template. For a new domain with limited authority, Semrush's example keeps competitors in the top 20 and sets keyword difficulty to "Very easy".
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Group keywords into topics. Judge topics, not rows. Ahrefs' template does this with a pivot table: in its example, one row holds a competitor page and the 120 keywords it ranks for. For AI answers, Semrush's advice is to "think in topics rather than individual prompts", because AI tools expand one prompt into several related queries. Google describes the same mechanism in its documentation on AI features: AI Overviews and AI Mode "may use a 'query fan-out' technique — issuing multiple related searches across subtopics and data sources".
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Check your own Search Console data. The Performance report shows clicks, impressions and average position, grouped by dimensions that include Queries and Pages. Its default view covers the past three months. Two patterns are worth looking for:
- A query you appear for, answered by a page that is not about it. People are already finding you for it, so this is usually a missing section or a missing page.
- A page that covers a topic but sits low for that topic's queries. This is usually a quality or intent gap.
Search Console counts impressions as how many times your site "appeared in Search results", so it cannot show you a topic you have no page for. That is what step 3 is for. Google's AI features documentation says sites appearing in AI Overviews and AI Mode are included in this report, "within the 'Web' search type".
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Add the gaps no tool shows you. Semrush lists social listening, surveys, sales calls, support tickets, product reviews and community discussions. Look for recurring questions, objections and comparisons. Its example: a running shoe brand finds people asking on Reddit whether knee pain is related to shoe cushioning. With no guide on choosing running shoes for knee pain, "that's a content gap."
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Check the AI answers for your topics. Semrush describes a manual prompt audit. Ask the questions your audience asks in ChatGPT, Perplexity and Google AI Mode, and note which brands are mentioned, which sources are cited, whether your brand appears and whether your content is cited. A mention and a citation are different gaps: the answer can name you without linking you. Our guides on keyword gaps in AI search and on choosing and running AEO prompts cover this step in depth.
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Read the pages that win before you decide. For each candidate topic, read the top-ranking pages and the pages AI answers cite. Semrush suggests comparing them with yours on recency, readability, expertise, experience and thoroughness.
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Decide one action per gap, and write it down. Ahrefs' test is whether you already have a page on the topic, which a
site:search answers. "If yes → you need to consider adding new sections to target common themes from the missing keywords. If not → you need to create a new page." Its own example is a landing-page article whose missing keywords mostly related to the definition of a landing page, so the fix was to add the definition. Ahrefs then recommends a task and a short content brief for each action, listing the sections and keywords to cover.
Which action fits which gap
| What you found | Action | Why |
|---|---|---|
| No page on a topic your audience needs | Write a new page | A topic gap. Nothing you have can rank or be cited for it. |
| A page exists, and a competitor's page on the same topic ranks for more keywords | Add the missing sections | A page-level gap. Ahrefs' landing-page example was closed by adding a definition. |
| A page exists but answers a different question from the one people ask | Rewrite it around the intent | An intent gap. More words on the wrong answer do not help. |
| A page is losing organic or AI traffic | Review it before rewriting it | Semrush calls these candidates for review rather than automatic rewrite targets, because seasonality, ranking changes, technical issues and AI Overviews can all cause a drop. |
| A page ranks but is not cited in AI answers | Make it easier to extract | Semrush's checks: a clear heading hierarchy, a direct answer under each heading, self-contained sections, and lists and tables for comparisons. |
| A popular topic outside your audience | Leave it | Ahrefs skipped the Moz example for this reason, and Google lists it as a warning sign. |
When not to fill a content gap
A gap list is a list of hypotheses, not a publishing schedule. Google's guidance lists questions that are "a warning sign that you should reevaluate how you're creating content". Several of them describe a gap list followed blindly:
- "Are you producing lots of content on many different topics in hopes that some of it might perform well in search results?"
- "Are you mainly summarizing what others have to say without adding much value?"
- "Are you writing about things simply because they seem trending and not because you'd write about them otherwise for your existing audience?"
- "Did you decide to enter some niche topic area without any real expertise, but instead mainly because you thought you'd get search traffic?"
Semrush ends its guide on the same point: "Keyword and prompt data can show possible opportunities, but your audience's needs should determine what you create or update first." For originality, it suggests first-party data, expert input, first-hand experience, specific examples and helpful frameworks such as a scoring system or decision tree.
What the sources emphasize, side by side
| Source | What it emphasizes | Main inputs | Who is speaking |
|---|---|---|---|
| Ahrefs, How to Do a Content Gap Analysis (Despina Gavoyannis, updated 17 February 2025) | Competitor keyword gaps, filtered and reviewed in a template; domain-level and page-level gaps | Ahrefs' Competitive Analysis export | Ahrefs sells the tool the guide uses. |
| Semrush, Content gap analysis: A step-by-step guide (Vlado Pavlik, 23 June 2026) | Audience-led analysis; four gap types; AI answers alongside search | Keyword Gap, its AI Visibility Toolkit, GA4, audience research | Semrush sells the tools the guide uses. |
| Google, Creating helpful, reliable, people-first content | Whether a page should exist at all; people-first versus search engine-first | Self-assessment questions | Google, describing what its ranking systems aim to reward. |
| Google, Search Console Performance report help | Your own query and page data | Clicks, impressions, CTR and average position by query and page | Google, documenting its free tool. |
Common content gap analysis mistakes
- Treating the export as the plan. A keyword list says what competitors rank for. It does not say what your audience needs from you.
- Picking competitors by brand. The sites that win your topics are often not the ones you sell against.
- Counting keywords instead of topics. A topic with 120 missing keywords can still be the wrong topic, as Ahrefs' Moz example shows.
- Writing a second page when the first needs a section. Check with a
site:search before you write. - Copying the top result. That swaps a topic gap for an originality gap.
- Reading every traffic drop as a content problem. Check seasonality, ranking changes and technical issues first.
- Leaving out AI answers. A site can cover a topic, rank for it, and still not be cited for it.
- Leaving out the audience. The questions in your sales calls and support tickets are gaps no tool can export.
Where TopCited fits
TopCited covers the AI-answer half of a content gap analysis, and the rewriting that follows it.
- Step 8, on a schedule. TopCited's content monitoring runs your query sets on a schedule you set (cron, with timezone support), records the brand mentions in the answers, and reports gap analysis: the queries where competitors appear and you do not. It also reports share of voice against the competitors mentioned alongside you.
- Quality and intent gaps on pages you already have. The CORE optimizer rewrites your existing content and scores it before and after, including keyword coverage, so the gap leads to a rewritten page rather than a list of issues.
- A starting point. To see where you stand, request a GEO audit through the form on our site.
For the competitor keyword export in step 3 you need a keyword database, such as those the two guides above describe. For the measurement side, see how to track brand mentions in AI search.
Frequently asked questions
Content gap analysis for SEO is the process of finding the topics your audience searches for and needs answered that your site does not cover, or covers worse than the pages that rank or get cited. The output is a set of decisions per gap: write a new page, add a section to an existing page, rewrite a page around the searcher's intent, or leave the gap alone.
A keyword gap is the list of keywords competitors rank for and you do not. A content gap is wider: a topic your audience needs that you do not cover, or cover badly. Semrush's guide treats keyword and prompt data as inputs to a content gap analysis rather than the entire strategy, because many audience questions never appear in keyword data.
Semrush's guide names four: a topic gap, where your site does not cover a topic your audience cares about; an intent gap, where you cover it but not in the way people want; a quality gap, where your page is thin, outdated or unclear; and an originality gap, where your page mostly repeats what competing pages say. Ahrefs' guide splits gaps into domain-level and page-level.
For competitor keywords, a keyword database such as Ahrefs' Competitive Analysis tool or Semrush's Keyword Gap. For your own queries and pages, Google Search Console's Performance report. For pages losing traffic, an analytics tool such as GA4. The audience research needs no tool: sales calls, support tickets, reviews and community discussions.
Relevance to your audience comes first. Then filter for demand and difficulty. Ahrefs' guide suggests requiring at least two competitors in the top 10, a minimum monthly search volume of 20, and a maximum Keyword Difficulty of 30 for easier wins. Then prefer gaps you can fill with something original.
No. Google's guidance on people-first content lists producing lots of content on many different topics in the hope that some of it performs as a warning sign. Leave gaps outside your audience, and expand an existing page rather than writing a second one on the same topic.
It should. Semrush's guide includes checking which brands AI answers mention and which sources they cite, and a Semrush study reports that pages ChatGPT search cites rank in organic positions 21+ for related queries almost 90% of the time. A page can rank in search and still be missing from AI answers.
For AI answers, yes. TopCited's content monitoring runs your query sets on a schedule, records brand mentions, and reports gap analysis, meaning the queries where competitors appear and you do not, along with share of voice. Its CORE optimizer then rewrites existing pages with before and after scores.
The short version
Content gap analysis for SEO finds the topics your audience needs that you do not cover, or cover worse than the pages that win. To run one that leads somewhere:
- Start from your audience, not from a tool export.
- Use competitor keyword gaps as one input, filtered hard and grouped into topics.
- Add your own Search Console data, your audience's questions and the AI answers for your topics.
- Name the gap type before you act: topic, intent, quality or originality.
- Choose one action per gap, and prefer a new section to a second page.
Leave the gaps that belong to someone else's audience.