A content gap analysis finds the searches your site should answer and doesn’t. Ahrefs’ guide defines it narrowly: “A content gap analysis is the process of finding topics your competitors have covered but you haven’t” (Ahrefs). We use a slightly wider version, because some of the best gaps are questions nobody in your space has answered well yet. Either way, it is one of the regular checks in an SEO content strategy: you run it before planning new pages, and again every few months.
How do you run a content gap analysis?
Six steps, one topic at a time. Doing the whole site at once produces a list too long to act on.
- Pick the topic and the real competitors. Search your main keywords and note the sites that rank. Those are your search competitors, and they are often not the businesses you compete with for customers.
- List what they rank for that you don’t. This is what keyword gap tools do (more on them below). Export the list.
- Add the questions people ask. Search the same keywords and read the People Also Ask box. Questions no page on your site answers are gaps, even when no competitor ranks for them either.
- Check what you already show up for. Search Console’s Performance report shows impressions, which Google defines as “How many times your site appeared in Search results,” and its queries dimension “groups your data by the search query users typed” (Search Console Help). A query with impressions but no page built for it is a gap Google has already spotted for you.
- Match each gap to your site. Before writing anything, check whether you already have a page on it. Ahrefs suggests Google’s
site:search for this. - Decide the fix and write the brief. New page, new section, or a rewrite. Each new page gets a content brief before anyone writes it.
What kinds of gap will you find?
Ahrefs’ guide says “there are two common types of content gaps you’ll need to fill: domain-level and page-level.” In practice we see four, and each has a different fix.
| Gap | What it looks like | Usual fix |
|---|---|---|
| Missing topic (domain-level) | Competitors have a page on it; you have nothing. | A new page, linked from the right parent. |
| Missing section (page-level) | You have the page, but it skips something the ranking pages cover. | Add a section to the existing page. |
| Weak page | You rank, but below competitors, or you get impressions and few clicks. | Rewrite so the page answers the question in its first lines. |
| Unanswered question | A question in People Also Ask that nobody answers well, you included. | A short answer page, or an H2 on the closest page. |
The second row is the one people miss. A new page for a subtopic you already cover splits your own rankings between two pages. When in doubt, add the section first.
Which tools help?
The big SEO suites have a report for step 2. As of 5 November 2026, here is what their own guides describe:
- Ahrefs. Its guide (updated 17 February 2025) uses the Competitive Analysis tool: add your domain and competitors, then “click the ‘Show keyword opportunities’ button to see all the keywords your competitors rank for, but you don’t.”
- Semrush. Its Keyword Gap guide (25 June 2024) says you can enter “up to four competitors’ domains” alongside your own. It sorts results into groups, including Missing (“keywords that all of the analyzed competitors rank for but you don’t”), Weak (“keywords your competitors are outperforming you for”) and Untapped (“terms at least one competitor is ranking for but you aren’t”) (Semrush).
For plans and prices, see their pricing pages. You can run a smaller version for free with Google’s own features and Search Console. Our page on free keyword research tools compares the free options.
For the question step, we built PAA Box, a free Chrome extension. It opens the People Also Ask box up to four levels deep and exports a CSV with each question’s depth and parent question, so you can sort the list next to your own page titles and mark which ones you already answer. It only reads the People Also Ask box; for keyword gaps you still need a keyword tool.
How do you decide which gaps to fill first?
Not every gap is worth closing. A few filters help:
- Fit. Would you write this page if search did not exist? Google’s guide to helpful content asks, “Are you writing about things simply because they seem trending and not because you’d write about them otherwise” (Google Search Central). A gap outside what you know is not your gap.
- Proof of demand. Queries you already get impressions for come first. Google is telling you it would show you for them.
- Size of the fix. Adding a section to an existing page is quicker than a new page and keeps the topic in one place.
- Coverage. Gaps inside a topic you already cover well are usually worth more than a scattering of new topics. That is how topical authority gets built, and the pages slot into your existing topic clusters.
The mistake to avoid: copying the gap
A gap report tells you a competitor has a page on something. It does not tell you to write the same page. Google’s SEO Starter Guide says “don’t copy others’ content in part or in its entirety” (Google Search Central), and its helpful content checklist asks, “Are you mainly summarizing what others have to say without adding much value?”
The better test is the one in that same checklist: “Does the content provide substantial value when compared to other pages in search results?” Fill the gap with your own examples, your own data, or a clearer answer. Otherwise you have closed a gap in your keyword list and opened one in your site’s usefulness.
Gap analysis is also a good source of ideas when you are stuck for what to write next. For the other main source, real questions on the results page, see how to find blog post ideas people actually search for.