AI SEO tools: what content scores measure, what AI visibility tracking costs and what Google says about AI-written pages (October 2026)

Three jobs under one label: search data, content scores and AI visibility tracking

Semrush and Ahrefs are search data suites. They crawl the web, estimate keyword volumes and backlinks, track rankings and audit sites. Both now also sell a way to see whether AI assistants mention your brand: Semrush through its SEO + AI Search plans, Ahrefs through Brand Radar. Semrush has belonged to Adobe since April 28, 2026.

Surfer, Clearscope, Frase and MarketMuse start from the text. You enter a keyword, the tool reads the pages that rank for it and rates your draft. Surfer gives a Content Score from 0 to 100 and an editor. Clearscope grades topic coverage. Frase scores the page against content already ranking for the query and also drafts with an AI agent that can publish on its own when you switch that on. MarketMuse builds a topic model from hundreds to thousands of pages and has been part of Siteimprove since a deal agreed in October 2024.

Our directory lists 15 tools in the SEO niche, 10 of them with SEO as the main niche. The others are writing, translation and traffic estimation tools that list SEO second. Pricing is mostly flat tiers tied to limits such as keywords, pages or prompts: 10 tools work that way, 1 charges per user and 2 quotes on request. 2 can host data in the EU. One of them is Surfer, which states on its pricing page that it is ISO 27001 certified and hosted in Europe. For a wider view of the field, see our SEO and content tools category.

Sources: [1][2][3][4][5][6][7][8][9]

What a content score measures, and what the two published studies found

Every score compares your draft with pages that already rank. Surfer says its Content Score reflects topical coverage, keyword usage, structure and depth against the top performers for your keyword. MarketMuse scores a page by how many subtopics from its topic model the text includes. Clearscope grades a draft for topic coverage in real time, and Frase shows one optimization score next to your writing plus a ranked list of what to add.

That design has a known weakness. Ahrefs, which sells its own AI Content Helper, writes that in many tools the score is largely based on how often you use the recommended keywords. In some, it says, you can paste the whole list, write nothing else and get an almost perfect score. A page that covers everything the top results cover also reaches full marks while adding nothing new. Google's guide for AI search asks for the opposite: a unique point of view, and not content that others have already said or that a generative model could easily produce.

Two studies put numbers on the link between score and rank, and both come from sellers of such tools. Surfer correlated its Content Score with position across 10,000 queries and about 1 million results and reports a Spearman correlation of 0.28, from 0.19 for instructional and short fact queries to about 0.30 for consequence queries. Ahrefs tested five tools (Surfer, Frase, NeuronWriter, Clearscope and its own) on 20 random keywords. It found weak correlations everywhere, with NeuronWriter and its own tool ahead and the other three very weak. Ahrefs notes that it had to turn Clearscope's letter grades into numbers with ChatGPT.

Taken together, a higher score goes with a higher position on average, but the relation is modest. Neither study shows that raising a score moves a page, and both authors sell what they measured. Surfer suggests aiming for a score of 70 to 85 instead of 100. Ahrefs suggests comparing with the pages you compete against: 95 against 20 is a gap worth closing, 79 against 80 is not. Read a score as a coverage check, not as a ranking forecast.

Sources: [10][11][12][13][6][14]

What AI visibility tracking costs: the unit is the prompt, and every vendor counts it differently

AI visibility tracking is the newest line item and the one with the least comparable pricing. Vendors sell it as a number of tracked prompts: questions that the tool asks ChatGPT, Gemini or Google's AI on a schedule to see whether your brand appears in the answer.

Semrush shows euro prices on its pricing page. The SEO plan costs €112.52 a month billed annually (€134 monthly). The SEO + AI Search plans add prompt tracking at €158.40 for 50 prompts a day, €238 for 100 and €436.99 for 200, with monthly prices of €190, €286 and €526. Surfer lists €82 a month billed yearly for 50 prompts refreshed daily as a standalone plan, €99 for 25 prompts refreshed weekly in Standard, €182 for 50 in Pro and €299 for 100 in Peace of Mind. Its entry plan, Discovery at €49, tracks none.

Ahrefs includes 5, 10 and 20 tracked prompts in Lite, Standard and Advanced, at €119, €229 and €419 a month with monthly billing. It also sells Brand Radar AI from €179 a month and custom prompt packages that count checks: one prompt on one platform in one location is one check. The €46.7 package includes 2,500 checks a month, which Ahrefs illustrates as 80 prompts daily on one platform.

Frase and Clearscope price in dollars. Frase includes 50 tracked prompts on ChatGPT and Google AI in Starter ($39 a month billed yearly), 200 prompts and Perplexity in Professional ($103) and 500 prompts with Claude and Gemini added in Scale ($239). Overage is optional and off by default, at $0.25 per extra prompt on Professional. Clearscope's Essentials plan ($129 a month, no minimum contract) tracks 50 queries across ChatGPT and Gemini, and Business ($399) tracks 300. MarketMuse publishes no prices, and its pricing page lists topic tracking, briefs and strategy documents rather than AI visibility.

So a prompt is not a unit. Semrush counts prompts tracked daily, Surfer prompts across all its models, Ahrefs checks per platform and location, Clearscope queries on two assistants and Frase prompts with a number of engines that rises by plan. Euro and dollar prices cannot be compared without an exchange rate, and the plans bundle different amounts of other tooling. Compare the cost per prompt only after you know what one prompt covers.

Sources: [1][3][2][5][4][6]

How far to trust AI visibility numbers: what SparkToro and Google say

The most cited test of AI answer consistency comes from SparkToro's Rand Fishkin and Patrick O'Donnell of Gumshoe.ai, published on January 28, 2026. Gumshoe.ai sells AI tracking tools, and the study discloses that partnership. About 600 volunteers ran 12 prompts through ChatGPT, Claude and Google's AI between November and December 2025, giving 2,961 runs. They report less than a 1 in 100 chance that ChatGPT or Google's AI returns the same list of brands when a prompt is repeated. For the same list in the same order, they see more like 1 in 1,000. Search Engine Journal points out that the work is not peer reviewed, and the authors leave open how many runs are needed for reliable visibility data.

The same study found a steadier signal: how often a brand appears across many runs. In a narrow category such as headphones, the top brands appeared in 55 to 77 percent of responses. The authors advise against reporting rank position in AI answers, call visibility percentage across many runs a reasonable metric and ask buyers to demand transparent, reviewable reports from tracking vendors.

Google's own guide adds a limit on what any tool can know. It says no third-party tool has access to Google's internal ranking or AI systems. Site owners should be wary of tools that promise ranking success or claim to use internal Google metrics. For AI Overviews and AI Mode, the guide points to the Generative AI performance report in Search Console. It also lists things you can ignore for Google Search: llms.txt files, chunking content, rewriting content just for AI systems and seeking inauthentic mentions. In its view "AEO" and "GEO" are still SEO.

That gives a practical reading. For Google's AI features, the first-party report is free. For ChatGPT, Claude or Gemini, a tracking tool is the only view you can buy, so treat its output as a sample: a share of runs, not a rank. Frase and Ahrefs bill by prompt or check, which suggests repeated runs, but none of the pricing pages we read says how many runs sit behind each reported number. Ask.

Sources: [15][16][14][17][18][8][7]

Google's rules for AI-written pages: scaled content abuse is the line

Google does not ban AI-written pages. Its spam policy defines scaled content abuse as many pages generated for the primary purpose of manipulating search rankings and not helping users, "no matter how it's created". Using generative AI tools to generate many pages without adding value for users is one of its named examples. Google announced the policy on March 5, 2024, and says it builds on its earlier rule on automatically generated content.

The AI search guide applies this to the workflow these tools encourage. Creating separate content for every possible variation of how people might search, including the related queries a model fans out to, primarily to manipulate rankings or AI responses, violates the policy. The risk sits in how you use a list of topic gaps, not in the list. Publishing a page for every suggestion is the pattern Google describes.

On drafting, Google says generative AI can be useful for researching a topic and adding structure to original content. It asks you to fact-check and review all AI-generated content before publishing, including title elements, meta descriptions, structured data and image alt text, because models predict a likely sequence of words and do not retrieve facts. Frase lets its agent publish on its own once you switch that on, and its Content Guard waits for your approval by default, so a review step is a setting you choose.

Sources: [19][18][20][14][5]

Before you buy: what to try for free and what to ask the vendor

Start with what is free. Google's Search Console shows how pages perform in AI features on Google Search at no cost. Ahrefs has a free plan, Semrush a free plan with one demo project and MarketMuse a free plan with 10 queries a month. Frase offers a 7-day trial without a credit card and Clearscope a 14-day free trial.

The choice then follows the job. If you need backlink and keyword data, a suite such as Semrush or Ahrefs covers it, and the AI visibility tier is an add-on to weigh separately. If your bottleneck is drafting and refreshing many pages, an editor such as Surfer, Clearscope or Frase fits, with the scoring caveats above. If you only need to know whether assistants mention you, price the prompts you actually need first, because that number drives the bill. Our marketing category lists the neighboring tools for content, email and social.

The checklist below collects the questions the comparison left open. Put them to each vendor in writing and keep the answers next to the pricing page you saw.

Sources: [14][2][1][6][5][4][15]