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Yonjun Jeong, Co-founder · Last updated: October 20, 2026

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What this article covers

When US buyers ask ChatGPT for SEO tools, it recommends Semrush first and Ahrefs second. In DecaGEO’s weekly measurement for Q3 2026 (July 5 to September 27), that held in all 3 weeks measured on GPT-5.4 and all 10 weeks measured on GPT-5.6 Terra. Below the top two, the order changes from week to week, so the useful question for the rest of the list is how often a tool makes the top 10, not where it sat in one week.
Summary for citation: In DecaGEO’s data for ChatGPT in the US (SEO category, weeks of July 5 to September 27, 2026), Semrush ranked #1 and Ahrefs #2 in all 3 weeks measured on GPT-5.4 and all 10 weeks measured on GPT-5.6 Terra. Semrush was recommended in 78.9% of answers in the GPT-5.4 weeks and 71.1% in the GPT-5.6 Terra weeks. Ahrefs went from 56.5% to 32.5%. In the week of September 27, SE Ranking (#3), Google Search Console (#4) and seoClarity (#5) followed. BrightEdge tied for #12.
Key takeaway: The top two are the same under both models. Besides Semrush and Ahrefs, eight tools made the top 10 in at least 7 of the 10 GPT-5.6 Terra weeks, and their order changed from week to week.

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Top 10 SEO tools ChatGPT recommends at a glance

Table 1: SEO tools ranked by DECA Score in the week of September 27, 2026 (GPT-5.6 Terra), with the number of weeks each made the top 10 under each model. DecaGEO, ChatGPT, US, English, weeks of July 5 to September 27, 2026. Definitions in How we measure. DECA Score is relative to the week’s #1, which is always 100. Ahrefs at 34.5 means ChatGPT recommended it about a third as strongly as Semrush that week. To see whether a tool was recommended more or less often over time, use the share of answers that recommended it. Table 2: Share of ChatGPT answers that recommended each tool, pooled by model period. Same 79 questions each week, one answer per question. DecaGEO, ChatGPT, US, English, SEO category, weeks of July 5 to July 19 (GPT-5.4) and July 26 to September 27, 2026 (GPT-5.6 Terra).
Line chart of weekly ranks over 13 weeks: Semrush stays at #1 and Ahrefs at #2 in every week. Google Search Console climbs from #10, #9 and #8 in the GPT-5.4 weeks to #3 or #4 in every GPT-5.6 Terra week. The other seven tools move between #3 and #14.

Weekly rank of the ten SEO tools ranked 1 to 10 in the week of September 27, 2026. The dashed line marks the week of July 26, the first week measured on GPT-5.6 Terra. DecaGEO, ChatGPT, US, English, SEO category, weeks of July 5 to September 27, 2026.

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The top 10, in detail

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1. Semrush (DECA 100)

Ranked #1 in all 3 GPT-5.4 weeks and all 10 GPT-5.6 Terra weeks. In the week of September 27, ChatGPT recommended it in 57 of 79 answers. See Semrush vs Ahrefs.

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2. Ahrefs (DECA 34.5)

Ranked #2 in every week of both periods. Its share of recommending answers fell from 56.5% in the GPT-5.4 weeks to 32.5% in the GPT-5.6 Terra weeks, and the distance to Semrush grew with it (see What changed at the July 26 model switch).

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3. SE Ranking (DECA 31.6)

Ranked #3 or #4 in all 13 weeks. In the week of September 27 it was recommended in 23 answers, one more than Ahrefs, and ranked below it because Ahrefs sat higher in the answers it appeared in.

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4. Google Search Console (DECA 26.9)

Ranked #10, #9 and #8 in the three GPT-5.4 weeks, then #3 or #4 in every GPT-5.6 Terra week. Its share of recommending answers went from 8.9% to 15.7%.

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5. seoClarity (DECA 21.6)

In the top 10 in 1 of 3 GPT-5.4 weeks and all 10 GPT-5.6 Terra weeks. Its weekly rank in the GPT-5.6 Terra period ranged from #5 to #10.

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6. BrightLocal (DECA 20.5)

In the top 10 in all 13 weeks, between #3 and #9. Its share of recommending answers went from 21.5% to 14.7%.

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7. Screaming Frog SEO Spider (DECA 19.9)

In the top 10 in 2 of 3 GPT-5.4 weeks and 7 of 10 GPT-5.6 Terra weeks. In the other three GPT-5.6 Terra weeks it ranked #11 to #13.

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8. Conductor (DECA 19.3)

#5, #5 and #4 in the GPT-5.4 weeks. In the GPT-5.6 Terra weeks it made the top 10 in 8 of 10, between #5 and #11.

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9. MarketMuse (DECA 15.8)

In the top 10 in 1 of 3 GPT-5.4 weeks and 9 of 10 GPT-5.6 Terra weeks, mostly between #7 and #9.

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10. Surfer (DECA 14.6)

In the top 10 in all 13 weeks and #6 in eight of them. Its lowest rank was #10, in the weeks of August 2 and September 27.

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What changed at the July 26 model switch

The week of July 26 was the first measured on GPT-5.6 Terra. The same set of 79 questions was asked in all 13 weeks.
  • The gap at the top widened. The distance between Semrush and Ahrefs in DECA points was 31.7 to 50.5 in the GPT-5.4 weeks and 52.6 to 67.4 in the GPT-5.6 Terra weeks. Semrush’s own share of recommending answers moved less (78.9% to 71.1%) than Ahrefs’ (56.5% to 32.5%).
  • Google Search Console moved up and stayed. From #8 to #10 before the switch to #3 or #4 in all ten weeks after it.
  • Mangools dropped out. It ranked #6, #8 and #9 in the GPT-5.4 weeks and did not make the top 10 in any GPT-5.6 Terra week, ranking between #13 and #55.

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Notable: BrightEdge

BrightEdge made the top 10 in 2 of 3 GPT-5.4 weeks and 1 of 10 GPT-5.6 Terra weeks. In the week of September 27 it tied for #12 (DECA 12.9). It was recommended in 11 of 79 answers that week, more than BrightLocal (10) at #6, and ranked lower because it appeared further down the answers that included it. DECA Score counts where in the answer a tool is recommended, not only whether it is. See BrightEdge vs Ahrefs and Semrush vs BrightEdge.

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What the top tools’ cited pages have in common

DecaGEO checks the tools’ own pages that ChatGPT cited in its SEO answers for on-page patterns. The category’s Weekly Breakouts tab shows these patterns by name for the tools that broke in or climbed that week. Here are five of them, counted across the ten tools ranked 1 to 10 in the week of September 27. Table 3: A tool counts if at least one of its cited pages that DecaGEO checked has the pattern. robots.txt is counted per site, not per page. DecaGEO, ChatGPT, US, English, SEO category, week of September 27, 2026. The first three are on the cited pages of nearly every top-10 tool. Schema.org types and Content freshness are on six, and Semrush, ranked #1 every week, has neither on its checked pages. These counts describe the pages ChatGPT cited. They do not show that a pattern moved any tool up the list.

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What you can do with this list

If you are choosing an SEO tool, the two tables tell you which names ChatGPT puts in front of US buyers and how steadily. This is a ranking of recommendations, not a review of features, so use it to build a shortlist and test from there.
  • Without an account, the live SEO ranking shows the current week, and each tool’s product page shows its Overview for that week.
  • With a free account, the Segment Position cards show buyer-condition rankings (segments). Clicking a card opens the questions behind it, and the Brand Ranking Trail shows the order ChatGPT recommended tools in each answer.
If your brand is in this category, the same pages show where you stand.
  • Without an account, search your brand in the header and open its Overview. The GEO Guide, under Dashboard in the site header, checks your own page for patterns like the ones in Table 3. It is free, and the first step needs no account.
  • With a free account, you get the latest four weeks, the Brand Ranking Trail for each question, every third-party source ChatGPT cited behind the recommendations in Off-Page Citations, the segment cards (including ones where you are not mentioned), and tracking for one brand.
  • Pro ($49 a month) adds ten weeks of data, full Chart History and CSV export.

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FAQ

Which SEO tool does ChatGPT recommend most? Semrush. It ranked #1 in all 3 weeks DecaGEO measured on GPT-5.4 and all 10 weeks measured on GPT-5.6 Terra (July 5 to September 27, 2026), and was recommended in 71.1% of answers in the GPT-5.6 Terra weeks. Is Ahrefs or Semrush ranked higher by ChatGPT? Semrush. Ahrefs ranked #2 in every week. In the GPT-5.6 Terra weeks Ahrefs was recommended in 32.5% of answers and Semrush in 71.1%. See Semrush vs Ahrefs. What is DECA Score? A 0 to 100 score for how often and how high ChatGPT recommends a tool within one category in one week. The week’s #1 is 100. Details are in How we measure and the methodology. Why isn’t BrightEdge in the top 10? In the week of September 27 it tied for #12. It was recommended in 11 of 79 answers, more than BrightLocal (10) at #6, but placed further down the answers that included it. Are these rankings stable? The top two were the same in all 3 GPT-5.4 weeks and all 10 GPT-5.6 Terra weeks. From #3 to #10, positions changed most weeks. Seven tools, Semrush and Ahrefs included, made the top 10 in every one of the 10 GPT-5.6 Terra weeks. Is this a features review? No. It ranks tools by how ChatGPT recommends them, not by feature quality, price or results.

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How we measure

The common method, including how questions are built and how DECA Score is calculated, is on the methodology page.
  • Window: 13 weeks, July 5 to September 27, 2026, ChatGPT, US, English. The weeks of July 5, 12 and 19 were measured on GPT-5.4 and the weeks from July 26 on GPT-5.6 Terra. Figures from the two periods are shown side by side and not combined.
  • Sample: the same 79 SEO questions every week, one answer per question, so 237 answers in the GPT-5.4 weeks and 790 in the GPT-5.6 Terra weeks.
  • DECA Score is shown for one week only, because it is relative to that week’s #1. The distance between #1 and #2 in DECA points can be compared across weeks.
  • Recommended in counts answers that recommended the tool. Passing or negative mentions are not counted.
  • Top-10 weeks counts weeks with a rank of 10 or better, including ties.
  • Page patterns are from the week of September 27, on each tool’s own pages cited in that week’s SEO answers.
  • The live board updates every Sunday, so it shows weeks after September 27.

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Sources