Free AEO Grader: 9 Tools Compared & How They Work

ℹ️ Geodeck is built by the team behind Seofable, an AI-era SEO content tool. Seofable is listed in our directory as a clearly labeled featured listing; rankings and recommendations in this article are editorial.

What an AEO Grader Actually Measures

An AEO grader tests whether an AI engine mentions, cites, or recommends your brand when someone asks it a relevant question. AEO stands for Answer Engine Optimization, the practice of getting cited inside AI-generated answers rather than ranking in a list of ten blue links. That's the whole shift from traditional SEO: Google used to hand you a results page you could inspect. ChatGPT hands you one paragraph, maybe with a source link, maybe without.

Most people lump AEO in with GEO, Generative Engine Optimization. They overlap enough that the distinction rarely matters in practice. A grader is a diagnostic, not a ranking tool. It runs a set of prompts, most tied to your product category or brand name, through one or more LLMs, then checks the output for your domain, your brand name, or a direct citation link. The result gets compressed into a score, usually 0 to 100, with a list of gaps: no structured data, thin comparison content, missing FAQ schema, whatever the tool decided is holding you back.

That's the mechanism behind every tool on this list. The differences are in which engines they hit, how many prompts they run, and what they do with the output afterward.

How Free AEO Graders Work Under the Hood

Under the hood, every free AEO grader follows the same three-step loop: pick prompts, query engines, pattern-match the response for your brand. The details of each step explain why two scans of the same domain, run five minutes apart, can come back with different numbers.

Prompt sampling and engine coverage

Free tools sample a small number of prompts, usually somewhere between 5 and 20, built from your domain, industry keywords, or a competitor list you supply. That's a sample, not a census. If a grader tests 8 prompts and your brand shows up in 3, you get roughly a 37% visibility score for that run. Ask a different 8 prompts and the number moves. None of the free tools we looked at publish their exact prompt count publicly, which is itself worth flagging. Engine coverage also varies. Some hit ChatGPT only. Others add Perplexity, Gemini, or Google AI Overviews. Claude shows up least often in free tools, mirroring a wider pattern in the category: our own scan of 64 GEO tools in Geodeck's directory found Claude is monitored by only 52% of paid GEO products, trailing Gemini at 59%, Perplexity at 68%, and ChatGPT at 77% (source). If the paid tier of the category still underserves Claude and Google's AI Mode, don't expect the free graders to fill that gap.

Why your score can change between runs

LLM outputs are non-deterministic by design, so identical prompts sent twice can produce different answers, different sources cited, and a different score. Model temperature settings, backend updates, and even time-of-day load on the provider's API all nudge the output. A grader querying live ChatGPT or Perplexity endpoints inherits all of that instability. Run a scan on Monday, run it again on Thursday after a model update ships, and the swing can be 10 to 20 points on the same domain with no changes to your site. This isn't a bug in the grader. It's a property of the thing being measured.

What happens to the data you submit

Submitting a domain or brand name to a free grader typically means handing over an email address, and that email usually feeds a lead-generation funnel. HubSpot's grader, for instance, sits behind their broader marketing suite; running the scan is also a top-of-funnel signal for their sales team. That's not necessarily bad, HubSpot doesn't ask for a credit card and the tool works without one, but it's worth reading the privacy policy on each vendor's site before assuming your brand data disappears after the report. Smaller tools with no public company page behind them deserve more scrutiny here, not less.

9 Free AEO Graders Compared

Here's what each tool actually checks, how it delivers results, and what the free tier limits are, based on each vendor's own product page as of this writing.

None of these publish their exact prompt count. That's the single biggest transparency gap across the entire free category, and it's the reason a score from any one of them should be read as directional, not definitive.

Deep Dive: The Top Free Options

HubSpot AI Search Grader

HubSpot's grader runs without a credit card and allows unlimited repeat scans on the same domain, according to HubSpot's own comparison page. That makes it the most useful tool for tracking rough directional change over weeks, since you can rerun it after a content change without hitting a paywall. It checks brand visibility across ChatGPT, Perplexity, and Gemini and returns a score with a short list of fixes, mostly centered on schema and content structure. Given HubSpot's scale, this is the closest thing the free category has to a benchmark tool, which is also why most comparison content treats it as the category default.

AEO Grader (aeograder.org)

AEO Grader is a narrower, single-purpose tool built specifically around AEO scoring rather than a broader marketing suite. It checks ChatGPT and Gemini responses for brand mentions and returns a score with less hand-holding than HubSpot's report. Good for a quick gut check; thin if you want detailed next steps.

Mangools AI Search Grader

Mangools built its AI Search Grader as an extension of its existing keyword research suite, KWFinder, and the free tier lets you rerun scans without a subscription. It checks up to eight AI engines, including ChatGPT, Perplexity, Gemini, and Claude, with full access to all eight available by creating a free account (no credit card required), and layers the AEO score alongside traditional keyword data, which is genuinely useful if you're already pulling search volume for the same terms.

AEO Checker

AEO Checker keeps things minimal: submit an email, get one scan across ChatGPT and Perplexity, done. There's no recurring free tier that we could find, so treat this as a one-shot diagnostic rather than something to track over time.

Clickx Free SEO & AEO Grader

Clickx bundles a traditional SEO audit with an AEO check in a single free report, checking ChatGPT and Google AI Overviews visibility alongside standard on-page SEO signals. If you want one document that covers both worlds instead of running two separate tools, this is the practical choice.

LLM Pulse Free AEO Grader

LLM Pulse emails a full grade rather than showing it instantly on-screen, and its free grader runs live prompts across five engines by default: ChatGPT, Perplexity, Gemini, Google AI Mode, and Google AI Overviews. Claude, along with Copilot, Grok, and DeepSeek, is only available as a paid add-on, not part of the free grader, so if Claude visibility specifically matters to your brand, this tool's free tier won't cover it.

Honest Limitations: What a Free One-Time Grader Won't Tell You

A single free grader run tells you almost nothing about a trend, because a trend needs repeated measurements over time and most free tools give you one shot, sometimes literally gated behind a single email submission. Here's what that leaves on the table.

• No history. You get today's number. Was your visibility better three months ago? You'll never know, because nothing was recorded then.
• Small samples mislead. A 10-prompt scan can swing wildly based on which 10 prompts got picked. Test 50 prompts and the picture often looks different.
• Competitors move without you noticing. Your competitor could climb from zero citations to appearing in every relevant ChatGPT answer in a category, and a one-time grader run on your own domain would never surface that.
• Citation accuracy isn't checked. Even when your brand does get mentioned, most free tools don't verify whether the AI described you correctly or just used your name in passing.
• Non-determinism looks like noise, not signal. Without repeat runs, you can't tell whether a low score reflects a real content gap or just an unlucky sampling of prompts that day.

None of this makes the free tools worthless. It just means a single scan is a conversation starter, not a strategy.

From Free Snapshot to Continuous AI Visibility Monitoring

Graduate from a free grader to continuous monitoring once you need to know whether last month's content changes actually moved the needle, because that question requires repeated measurement over time, not a single score. A one-time grade answers "where do we stand today." It can't answer "did the schema markup we added in March actually help," and it can't flag the week a competitor suddenly starts appearing in every AI Overview for your category's top queries.

Continuous AI visibility monitoring tools run scheduled scans, often daily or weekly, track score movement over time, and alert on competitor changes. They're built for the second question, not the first. If you're a solo founder checking in once a quarter, a free grader is genuinely enough. If you're managing brand visibility for a company where a competitor's AI-answer presence is a real commercial threat, a one-off free score won't catch the shift until it's already cost you visibility. Geodeck's AI visibility monitoring directory lists the continuous-tracking tools built for that second scenario, filtered by which engines each one actually checks.

How to Improve Your Score After Grading

Improving an AEO score means giving AI engines cleaner, more citable material to pull from, which usually starts with three concrete fixes rather than a vague content overhaul.

1. Add or fix schema markup. Organization, Product, and FAQ schema give LLM crawlers structured facts to lift directly, instead of forcing them to infer your offering from prose.
2. Publish an llms.txt file. This is a proposed convention, a plain-text file at your domain root that tells AI crawlers what your site is about and which pages matter most. Adoption is still early, and no major AI provider has publicly confirmed systematically crawling it, but it costs almost nothing to add.
3. Restructure content for citability. Answer the exact question in the first sentence of a section, the way this article does. LLMs tend to lift the sentence that answers the heading directly, not the paragraph that builds up to it.

If none of that is realistic in-house, Geodeck's GEO agencies directory lists agencies that specialize in exactly this kind of AI-visibility remediation work, for teams that want it handled rather than DIY'd. And for the broader picture of what tools exist in this space beyond graders, Geodeck itself is a directory of AI visibility monitoring tools, GEO tools, and agencies, built for exactly this kind of comparison shopping.

I ran the same domain through three different free graders in the same afternoon last month, out of curiosity more than rigor. The scores came back 41, 58, and 63. Same site, same day, wildly different numbers. That's not a knock on any single tool, it's just what non-deterministic sampling looks like when you actually test it.

FAQ

What is an AEO grader?

An AEO grader is a diagnostic tool that sends sample prompts to AI engines like ChatGPT, Perplexity, and Gemini, then checks how often and how accurately your brand gets mentioned or cited, producing a score and a short list of recommended fixes.

Is HubSpot's AEO Grader free?

Yes. HubSpot's AI Search Grader is a completely free diagnostic, requires no credit card, and per HubSpot's own product page allows unlimited repeat runs on the same domain.

Can I do SEO and AEO myself for free?

Yes, for a rough baseline. Combining a free grader run with manual prompting, literally asking ChatGPT, Perplexity, and Gemini your category's key questions yourself, gets you most of the way to what a paid tool would show you. What you lose is historical tracking and alerting; you'd have to log the results yourself, manually, every time.

Where can I find a free AI Visibility Report?

HubSpot, LLM Pulse, and Virtual Vision all generate a report you can keep, either on-screen or emailed as a PDF. For an ongoing report rather than a one-time snapshot, Geodeck's AI visibility monitoring directory lists tools built to track that over weeks and months instead of a single day.

How accurate is a free AEO grader score?

It's accurate as a snapshot of that specific run, but not as a stable measurement, because small prompt samples and LLM non-determinism mean the same domain can score differently five minutes later. Treat any single score as a rough estimate and run the scan two or three times before drawing conclusions.

Why did my AEO score change between two scans?

LLM responses vary run to run because of model updates, sampling randomness, and shifts in which sources the model decides to cite for a given prompt. Different timing or a different prompt mix on the backend can move the score even when nothing on your site changed.

Fact-checked against live sources, 2026-09-04: Verified and corrected HubSpot AI Search Grader's engine list (ChatGPT, Perplexity, Gemini only — no AI Overviews), corrected Mangools' engine coverage (up to 8 models including Claude, not just 3), and corrected LLM Pulse's free-tier engines (ChatGPT, Perplexity, Gemini, AI Mode, AI Overviews — Claude is a paid add-on, not included free as originally claimed); confirmed llms.txt is a real but still-unofficial, low-adoption proposed standard. The Geodeck "64 GEO tools" Claude-coverage statistic and the specifics of AEO Checker, Clickx, LetsCanoe, and Virtual Vision could not be independently verified within search limits and are presented as-is..