What is an LLM SEO check tool?

An LLM SEO check tool evaluates whether your website's content answers the queries users ask AI search engines. The most useful tools measure content relevance (query coverage, depth, sub-intent coverage), not just structural signals. Our research found structural checks alone predict citations at r=0.009 - content relevance predicts at AUC 0.915.

Which LLM SEO tool should I start with?

Start with a content relevance diagnostic to understand which queries your content covers and where the gaps are. Run a free scan at getaisearchscore.com for a Content Relevance Score across five components. Once you know your content gaps, choose a monitoring tool to track citation progress and a content tool if you need help writing.

Do I need both a diagnostic tool and a monitoring tool?

Yes - they serve different purposes. A content relevance diagnostic tells you what to fix (which queries you don't answer, which sub-intents you miss). A monitoring tool tracks whether AI engines actually cite you over time. Most teams need both, but the diagnostic should come first.

Are traditional SEO tools enough for AI search optimization?

No. Traditional tools track keyword rankings and backlinks, which don't predict AI citations. They don't measure content-query relevance, sub-intent coverage, or AI crawler access. You need at least one dedicated LLM SEO tool alongside your traditional stack. But be critical: ask any tool vendor for published evidence that their signals predict citation outcomes.

Recommended LLM SEO Check Tools in 2026: What Each One Actually Does

Bias disclosure: We built one of the tools reviewed below (LLM SEO Check at getaisearchscore.com). We will be as fair as we can, but you should know that upfront. Take our assessment of our own tool with appropriate skepticism.

LLM SEO - sometimes called Generative Engine Optimization (GEO) - is a new discipline, and the tooling landscape is growing fast. Dozens of products now claim to help you “optimize for AI search”. We have tested most of them and built one ourselves. Here is what we have learned about what each tool actually does, where each is genuinely useful, and the hard truth none of us in this space talk about enough.

Before we get into individual tools, we need to say something uncomfortable about this entire category.

The Elephant in the Room

We ran a study of 441 domains across 14,550 domain-query pairs, measuring whether structural readiness scores - the kind every audit tool produces, ours included - actually predict whether a site gets cited by AI engines. The correlation was r=0.009, p=0.849. Effectively zero.

No threshold effect. No necessary-condition relationship. Not even within the same topic vertical. What did predict citations was content relevance: same-topic citations were 62x more likely than cross-topic. A follow-up classifier built on BM25 plus embedding similarity reached AUC 0.915 on 13,140 domain-query pairs. That finding drove us to rebuild our own product around content relevance rather than pure structural checks.

This does not mean every tool below is useless. Structural hygiene is a reasonable baseline for any website. But most tools in this space - ours included - have not published before/after case studies showing that applying their recommendations produces measurable lift in citation rates. We are running that experiment on our own site now. Keep that in mind as you read the recommendations below.

The 4 Categories of LLM SEO Tools

Every tool in this space falls into one of four categories. Understanding the category matters more than comparing feature lists, because buying the wrong category is the most expensive mistake.

1.
Audit Tools - Crawl your site, check for AI-specific signals, produce a diagnosis. Useful for finding obvious technical problems like blocked crawlers or missing structured data.
2.
Monitoring Tools - Track whether AI engines are citing your site over time. They show trends but do not explain causes.
3.
Content Optimization Tools - Help you write content that covers topics more thoroughly. Originally built for traditional SEO, now repositioned for AI.
4.
Traditional SEO + AI Features - Classic SEO platforms with AI overlays bolted on. Good at what they have always done. The AI features are mostly new and unproven.

Category 1: AI Search Audit Tools

Audit tools check whether your site has the structural signals that the industry believes matter for AI citation: structured data, crawler access, content format, entity trust. We say “believes” deliberately - see the elephant above. That said, if your robots.txt blocks GPTBot entirely, fixing that is obviously a prerequisite. Audit tools catch that kind of problem well.

LLM SEO Check (getaisearchscore.com)

This is our tool. The current version runs a five-component Content Relevance Score: Query Coverage, Content Depth, Sub-Intent Coverage, Citation Reality (on paid scans), and Technical Health (the legacy 26-check technical audit rolled into one subcomponent). The free tier includes the full four-component audit - not a teaser. The €149 one-time Starter tier adds Perplexity citation monitoring and a human expert consultation with prioritized rewrite tasks. Limited slots per month because Starter is high-touch.

What it does well: Query fan-out analysis with sub-intent coverage (the signal our own research identified as the strongest predictor of citations, AUC 0.915). Free tier gives the full content relevance diagnostic. Published null findings alongside positive ones.
Honest limitation: We have not yet published a before/after case where a real site applied our recommendations and saw citation rate rise. That experiment is running on our own site right now. Perplexity is the only citation platform we monitor.
Best for: SMBs and content-heavy sites that want a deep content relevance diagnostic and (optionally) a human expert to walk through the results
Price: Free (full content relevance audit), €149 one-time Starter consultation

HubSpot AEO Grader

HubSpot released a free AI Engine Optimization grader. It checks some of the same structural signals - content structure, schema markup, answer-readiness. The advantage is that it comes from a well-known brand with a large existing user base, and it is free.

What it does well: Free, simple, comes from a trusted brand. Good entry point for teams already in the HubSpot ecosystem.
Honest limitation: Less depth than dedicated tools. Like all audit tools in this space, no published evidence that improving their metrics leads to more citations.
Best for: HubSpot users who want a quick directional check without adding another vendor
Price: Free

Passionfruit

A GEO audit platform with a comprehensive checklist approach. Passionfruit provides good educational content alongside its audit, walking users through the reasoning behind each factor. The checklist format is thorough and well-organized.

What it does well: Educational approach. If you want to understand the "why" behind each check, Passionfruit explains the reasoning, not just the result.
Honest limitation: Manual checklist, no automated scoring engine. Requires more time and effort than automated tools.
Best for: Teams that prefer a learning-oriented approach and have time for manual review
Price: Subscription-based

WordLift

WordLift has been in the structured data / knowledge graph space longer than most competitors. Their AI SEO agent approach focuses on building entity-level structured data and knowledge graphs that help AI engines understand your content semantically. They have real technical depth in the schema markup area.

What it does well: Deep expertise in structured data and knowledge graphs. If your problem is schema markup quality, WordLift has the most sophisticated approach.
Honest limitation: Premium pricing. The knowledge graph approach is technically sound but whether it translates to more AI citations is unproven (same caveat as every tool here).
Best for: Publishers and content-heavy sites that want advanced structured data, not just basic schema
Price: From $59/month, enterprise tiers available

A Note on LightSite AI

LightSite AI offers managed GEO services and has promoted something they call the "WACP standard" for AI search optimization. I should note: WACP is not an industry standard recognized by any standards body. It appears to be a proprietary framework that LightSite created and branded as a "standard." That does not mean their service is bad - I have not used it - but calling a proprietary checklist a "standard" is a marketing choice you should be aware of when evaluating their claims.

Category 2: AI Citation Monitoring

Monitoring tools track whether AI engines are citing your site over time. They answer "is it happening?" but not "why?" In my view, this is actually the most defensible category - at least you are measuring the real outcome (citations) rather than proxy metrics.

Otterly.ai

Otterly.ai tracks brand visibility across ChatGPT, Perplexity, and Google AI Overviews. They have a Semrush partnership which gives them distribution and credibility. Their brand-level monitoring is particularly well-executed - competitive benchmarking across AI platforms is genuinely useful if you manage a brand.

What it does well: Brand-focused AI visibility tracking. Multi-platform coverage. The Semrush integration is a smart move that gives them reach.
Honest limitation: Brand-level focus means less granularity for page-by-page diagnosis. Monitoring shows trends but does not explain causes.
Best for: Brand managers who need to track and report on AI search presence
Price: From $39/month

LLMrefs

An AI search analytics platform built specifically for tracking mentions and citations across AI engines. LLMrefs has built a large user community (they claim 10,000+ marketers) and their analytics dashboards are purpose-built for this use case rather than adapted from traditional SEO.

What it does well: AI-native analytics built from the ground up. Large community means more shared learnings. Citation tracking is their core focus, not a bolt-on.
Honest limitation: Monitoring only - does not diagnose technical issues or recommend fixes. You need a separate tool for that.
Best for: Marketing teams focused specifically on citation rates and competitive positioning in AI search
Price: From $49/month

Conductor

Enterprise SEO platform that has added AI search monitoring on top of its traditional capabilities. Conductor tracks AI crawler visits, monitors brand visibility across AI platforms, and provides executive dashboards. If you are already a Conductor customer, the AI features add value without requiring a new vendor.

What it does well: Enterprise workflow integration. If your org already uses Conductor, adding AI monitoring is seamless. Executive reporting is polished.
Honest limitation: Enterprise pricing. The AI features are additions to a broad platform, not deep AI-specific diagnostics. Overkill for SMBs.
Best for: Enterprise teams with existing Conductor subscriptions
Price: Custom enterprise contracts (typically thousands per year)

Category 3: Content Optimization for AI

Content optimization tools help you write more thorough, better-structured content. They were originally built for traditional SEO and have been repositioned for AI search. Here is where I think they actually have the strongest case - my research found that content relevance to the query is the strongest predictor of citation. Tools that help you cover topics more completely may genuinely help, though none have published causation data.

Surfer SEO

Content optimization platform that uses NLP analysis to score your content against top-ranking pages. Surfer analyzes structure, keyword usage, heading patterns, and topic coverage, providing real-time scoring as you write.

What it does well: Real-time content scoring while you write. Good at ensuring topical completeness. Mature product with years of iteration.
Honest limitation: Does not check structured data, crawler access, or entity trust. "AI optimization" is mostly the same content optimization they have always done, rebranded.
Best for: Writers and content teams who want data-driven content quality benchmarks
Price: From $89/month

Clearscope

Content grading platform focused on topical completeness. Clearscope assigns a letter grade based on semantic coverage - how well your content covers the expected topics for a given query.

What it does well: Clean interface, clear grading system. Good at identifying topic gaps in your content.
Honest limitation: Expensive for what it does. Content-only focus with no technical infrastructure checks.
Best for: Teams with dedicated content writers who need quality benchmarking
Price: From $170/month

MarketMuse

Content strategy and gap analysis platform. MarketMuse identifies topics your site should cover but does not, and suggests content plans to fill gaps. The strategic planning features are genuinely useful for editorial teams.

What it does well: Content gap analysis is the real strength here. Helps you find topics where you have no content but should.
Honest limitation: Strategy-focused, not execution-focused. Does not help with technical signals.
Best for: Content strategy planning and editorial calendar development
Price: From $149/month (free limited tier available)

Category 4: Traditional SEO with AI Features

Traditional SEO platforms have added AI-related features. These tools remain excellent at their core purpose - keyword research, backlink analysis, rank tracking. The AI features are mostly new and should be evaluated accordingly.

Semrush

The most comprehensive traditional SEO platform. Semrush excels at keyword research, competitive analysis, backlink auditing, and position tracking. Their AI features include content suggestions and some AI search visibility data.

What it does well: Best-in-class traditional SEO. If you need one platform for keyword research, backlinks, and rank tracking, Semrush is hard to beat.
Honest limitation: AI features are add-ons, not the core product. Does not check AI crawler access, schema completeness for AI extraction, or answer-ready content format.
Best for: Teams that need comprehensive traditional SEO and want some AI visibility in the same tool
Price: From $129/month

Ahrefs

Primarily known for backlink analysis and keyword research. Ahrefs provides deep competitive intelligence and content exploration. Their Content Explorer can surface content opportunities relevant to AI search trends.

What it does well: Best backlink analysis in the industry. Content Explorer is useful for finding what content is getting traction.
Honest limitation: Core strength is links and keywords, not AI-specific signals. AI features are minimal compared to dedicated tools.
Best for: Teams focused on backlink strategy and competitive keyword analysis
Price: From $99/month

Full Comparison Table

Tool	Category	Free Tier?	AI-Specific Checks	Score Model	Citation Tracking	Proven Causation?
LLM SEO Check*	Audit + consulting	Yes (full audit)	5-component Content Relevance	0-100 weighted	Yes (paid)	AUC 0.915 observational
HubSpot AEO Grader	Audit	Yes	Basic checks	Grading system	No	No
Passionfruit	Audit	Limited	Manual checklist	No unified score	No	No
WordLift	Audit	No	Schema + knowledge graph	Entity-based	No	No
Otterly.ai	Monitoring	Trial	Brand tracking	Brand visibility score	Yes	N/A (measures outcome)
LLMrefs	Monitoring	Limited	Citation tracking	Analytics dashboard	Yes	N/A (measures outcome)
Conductor	Monitoring	No	Crawler log analysis	Multiple metrics	Yes	N/A (measures outcome)
Surfer SEO	Content	Trial	Content optimization	Content score	No	No
Clearscope	Content	No	Topic coverage	Content grade	No	No
MarketMuse	Content	Free limited	Gap analysis	Content score	No	No
Semrush	Traditional+AI	Trial	Limited AI overlay	Various metrics	No	No
Ahrefs	Traditional+AI	Trial	Limited	DR, UR	No	No

* Our tool. See bias disclosure at the top.

What We Would Actually Recommend

Given the evidence gap described above, here is our honest take on how to approach this space:

1
Fix obvious technical blockers for free. Run any free audit tool - ours, HubSpot's, or even a manual check of your robots.txt and schema markup. If GPTBot is blocked or your content is entirely JavaScript-rendered, fix that. This is basic hygiene, not a competitive advantage.
2
Invest in content relevance. This is the one signal that actually showed up in our data (62x same-topic effect, AUC 0.915 classifier). Content that thoroughly covers a query - including its sub-intents - is far more likely to be cited than content that scores well on structural metrics but is tangential. Content optimization tools (Surfer, Clearscope, MarketMuse) can help with topical depth. Our own tool measures query-content relevance directly through query fan-out decomposition.
3
Monitor actual citations, not proxy scores. If you are going to spend money, monitoring tools (Otterly.ai, LLMrefs) measure the real outcome. A citation tracking tool tells you if something is working. A score tells you if you match someone's theory about what should work.
4
Be skeptical of any tool claiming proven results. Including ours. This space is too new for anyone to have definitive answers. Anyone telling you they have cracked the code is either wrong or selling something. Or both.

Common Mistakes When Choosing LLM SEO Tools

Three patterns we see repeatedly:

Confusing proxy metrics with outcomes. A high audit score is not a citation. A good content grade is not a citation. Only monitoring tools (or Citation Reality on paid tools like ours) measure citations. Everything else measures inputs that correlate at best.
Over-investing in structural optimization. We say this as people who built a structural audit tool: if your structural hygiene is baseline acceptable (crawlers not blocked, basic schema present, content not behind JS), spending more time on structural perfection has diminishing returns. Spend that time on content relevance instead.
Buying tools before understanding the problem. Run a free audit first. You might find your site is already fine structurally and the real issue is content relevance - in which case the tool you need is a content platform or a content relevance audit like ours, not another structural checker.

Budget Guide

Given the evidence gap, we would be conservative with spending:

€0/month: Run a free audit (ours or HubSpot's). Fix obvious blockers manually. For most sites, this is sufficient. Seriously.
$40-$100/month: Add one monitoring tool (Otterly.ai or LLMrefs) if you need to report on AI search visibility to stakeholders or want to track trends.
$100-$250/month: Add a content optimization tool if monitoring shows low citation rates and you suspect content depth or coverage is the issue.
€149 one-time: Our Starter consultation replaces a multi-month retainer with a single human-led review plus prioritized rewrite tasks. Useful when you want expert interpretation without ongoing monthly spend.
$250+/month: Only if AI search is a strategic priority and you have the team to act on the data. Combine monitoring + content optimization + one-off consultations.

Bottom line: Every tool in this space, ours included, is working with incomplete knowledge about what actually drives AI citations. The honest tools will tell you that. The less honest ones will claim certainty they do not have. Use free tiers to fix obvious problems, invest in content relevance, monitor actual outcomes, and stay skeptical of anyone - including us - claiming they have the answer.

If you want to check your site's content relevance and structural baseline, run a free LLM SEO Check audit. The free tier includes the full four-component Content Relevance Score. If you want a human expert to walk through the results, book a Starter consultation (€149, limited slots per month).

For more on the research behind these conclusions, read our honest review of our own scoring model and the content relevance study (AUC 0.915).