Why do Semrush and Ahrefs show different AI visibility scores for the same brand?

Each vendor runs its own prompt corpus, sampled at its own time, with its own counting rules for what counts as a mention versus a citation. Two tools can therefore report different numbers for the same brand on the same day, and both can be accurate about their own sample. Compare trends within a single tool over time; never compare absolute scores across two tools, because they do not measure the same thing.

Is there a free AI search visibility checker that works without signing up?

Yes. Semrush states on its own page that you can use its free checker three times per day without registering or creating an account, and Ahrefs offers a free snapshot as well. Daily limits apply and vary by vendor. The manual alternative — a small prompt set run yourself across ChatGPT, Perplexity and Gemini — needs no tool or account at all and keeps every query on your own machine.

Can I check my AI visibility manually without any tool?

Yes. Write a short list of buying-intent prompts — the questions a customer would actually ask in your category — and lock it. Run each prompt in ChatGPT with search, in Perplexity and in Gemini, and record whether your brand is mentioned, whether a page of yours is cited, and which competitors appear. Treat one pass as directional, because answers vary between runs; the value comes from rerunning the same set later.

What happens to my brand or domain data when I run a free check?

When you submit a brand or domain to a free checker, that query enters the vendor's systems and is handled under the vendor's terms, which vary from one company to another. Read them before submitting anything sensitive, such as an unlaunched brand name. The manual check is the only option where nothing leaves your machine: you type the prompts into the engines yourself and keep the results in your own spreadsheet.

How often should I re-run a free AI visibility check?

Monthly is a reasonable rhythm for most brands, always on the same locked prompt set. Because engines vary their answers from run to run, a single check is a snapshot, and a change between two snapshots can be noise. Repeated runs on identical prompts are what make a movement meaningful. If you report to clients or track competitors, monthly manual checks usually stop scaling and monitoring becomes the better fit.

Check Your AI Search Visibility for Free (and What Checkers Miss)

Yes, you can check your AI search visibility for free: manually in about fifteen minutes, or with a free checker that runs without an account. One limit is worth stating up front: a free check tells you whether your brand appears in AI answers, not why competitors appear instead or what to change.

What a free AI visibility check actually measures

AI search visibility is whether, and how, your brand appears in the answers of ChatGPT, Perplexity, Gemini, Claude and Google's AI Overviews and AI Mode. Buyers increasingly ask these assistants for shortlists and recommendations instead of clicking through result lists. In a Pew Research Center study published in July 2025, users who encountered an AI summary clicked a traditional search result link in 8% of all visits, while those who did not clicked nearly twice as often, in 15% of visits.

Before running any check, separate a mention from a citation. A mention is your brand named in the answer text; a citation is a link to one of your pages as a source. Free checkers count the two differently; we cover the difference between an AI mention and an AI citation separately.

Separate the tools too. The word checker covers two unrelated families: prompt-based checks ask engines real questions and record who appears in the answers, while readiness checks score your site's crawlability and markup without asking any engine anything. A high score in one family says nothing about the other, and platform coverage differs from tool to tool.

Run the check yourself in about fifteen minutes, no signup

Ten prompts, three engines, one spreadsheet

Write eight to ten prompts a buyer in your category would actually ask. Lock the list. Run each prompt in ChatGPT with search enabled, in Perplexity and in Gemini. For every run, record whether your brand is mentioned, cited, or absent, and which competitors appear. This requires no account and no tool, and no data about your brand leaves your machine.

Treat the result as directional, not as a measurement: engines vary their answers between runs, so a single pass per prompt is a snapshot. The strength of the manual check is control. It is the only free option whose methodology you define completely and can rerun identically next month.

Verify the AI crawlers can reach your site

Open your robots.txt and read it. OpenAI's documentation lists GPTBot and OAI-SearchBot as separate robots.txt tokens, each setting independent of the others, so check both (verified on 29 September 2026 in OpenAI's bot documentation). Anthropic confirms its bots honour industry standard robots.txt directives, so a disallow aimed at ClaudeBot is respected (verified on 29 September 2026 in the Claude Help Center). Look for PerplexityBot and Perplexity-User in the same file. A blanket disallow that catches these tokens can keep citing engines away from your pages.

The free checkers, and why their scores disagree

Semrush's free-tool page states you can use the tool three times per day for free, without registering or creating an account (verified on 29 September 2026). Ahrefs' page describes a free snapshot showing which platforms mention your brand most, and which ones don't (verified on 29 September 2026). Both are prompt-based checks; readiness checkers are the third free route.

Option	What it measures	Limits	What it cannot show
Manual prompt check	Mentions and citations on your own prompts	Your time; one run is a snapshot	Trends, until you rerun
Free prompt-based checker	Mentions and citations on the vendor's sample	Daily caps; coverage varies by vendor	Why competitors win each prompt
Free readiness checker	Site crawlability and markup, no engine queried	No answer-level data at all	Whether you appear anywhere

Two reputable checkers can return different numbers for the same brand because each vendor samples its own prompt corpus, at its own time, with its own counting rules for mentions versus citations. Trust the trend within one tool; never compare absolute scores across two.

Also, a query you submit to a free checker enters the vendor's systems under its terms; the manual check is the only route where nothing leaves your machine.

What no free check tells you

A free score answers one question: whether you appear. Start with the competitor gap: your number does not show which competitors are cited on the prompts you lose, or on which engines. Semrush documents the report that shows how AI platforms position your competitors compared to your brand in its AI Visibility Toolkit, a separate product from the free checker (verified on 29 September 2026 in Semrush's toolkit documentation). That benchmarking layer is what turns a check into a plan; we explain how to benchmark your AI visibility against competitors in a dedicated article.

Next, the why. An absence can come from crawler blocking, a thin entity footprint, missing third-party coverage, or an engine simply preferring another source. Telling these apart requires per-prompt, per-engine evidence over repeated runs, which no single free score carries.

Finally, the cases where one number misleads. A score can move while your citations stay flat, because the vendor refreshed its prompt corpus or the engine changed; a single-number drop is not proof you lost visibility, but repeated runs on a locked prompt set are. One score also blends languages, markets and entities: a business with several locations or sub-brands under one name should check per language and per entity.

Where to start this week

Spread the work over five days. Monday, write your eight to ten buying-intent prompts and lock the list. Tuesday, run the manual check across the three engines and record every mention, citation and competitor. Wednesday, read your robots.txt for the crawler tokens above. Thursday, run one free checker as a second data point, and keep its number separate from yours. Friday, list the prompts where competitors appear and you do not. That gap list is your work queue, and with the locked prompt set it is reusable next month.

A free check is enough when you track one brand and want an occasional pulse. It stops being enough when you have clients, competitors to follow, or month-over-month reporting to produce; at that point, read how to automate your AI visibility checks. To see which prompts already cite your competitors and not you, run a free Namedrop scan as your next step.