9 Free AI Visibility Checkers Compared

The best free AI visibility checker depends on whether you want to measure brand mentions or on-site crawler readiness. At Layer3Labs, we run on-site readiness checks across the sites we build and operate, and a mention check alone never shows a robots.txt block.

Most free tools offer one-off diagnostic snapshots rather than continuous tracking. Use this comparison of nine free checkers to match your immediate question to the right free diagnostic before paying for recurring software.

On-site readiness checkers vs. Prompt-based mention checkers: Side-by-Side

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The Short Answer: Which Free Checker Measures What

Prompt-based mention checkers query generative models directly. Semrush AI Search Visibility Checker fits domain-level brand discovery, Ahrefs Free AI Visibility Checker fits search-backed prompt snapshots without an account, HubSpot AI Search Grader fits brand sentiment analysis, Mangools AI Search Grader fits quick share-of-voice checks across ChatGPT, Mistral Small and Llama, and GoBIG Systems Free AI Visibility Checker fits local business competitor discovery.

On-site readiness checkers test your technical infrastructure. The Adobe AI Content Visibility Checker Chrome extension checks single-page rendering without JavaScript, Layer3Labs AI Visibility Checker provides a 100-point crawler readiness score and firewall test, Am I Visible on AI offers quick baseline technical audits, and AI Visibility Checker runs 10 heuristic indexability checks. For broader ongoing tracking, compare full suites in our best AI visibility tools comparison.

• Semrush: Best for domain-level visibility scores and top cited pages across Google and OpenAI engines.
• Ahrefs: Best for inspecting prompt-level mention counts and cited competitor domains with zero account registration.
• HubSpot: Best for evaluating training-data brand sentiment and perception scores out of 100.
• Mangools: Best for comparing brand share of voice across ChatGPT, Mistral Small and Llama 3.3 without an account.
• GoBIG Systems: Best for local contractors and service businesses checking city-specific recommendations in ChatGPT.
• Adobe: Best for developers and technical SEO leads diagnosing dynamic JavaScript rendering barriers in the browser.
• Layer3Labs: Best for site owners checking 11 AI crawler permissions, llms.txt files, and OAI-SearchBot firewall access.
• Am I Visible on AI: Best for unlimited free re-runs with a banded readiness score.
• AI Visibility Checker: Best for a 10-check score with a paid fix guide if you want one.

Prompt-Based Mention Checkers

Prompt-based mention checkers test how generative engines respond when asked queries related to your brand, niche, or product category. These tools run queries against models and extract whether your entity appears in the output, what sources get cited, and which competitors show up alongside you.

The Semrush AI Search Visibility Checker takes a domain URL and queries ChatGPT, Gemini, Google AI Overviews, and Google AI Mode. It returns an AI Visibility Score from 0 to 100, estimated audience reach, top cited pages, best-performing topics, and competitor comparisons. Users receive three free checks per day without creating an account. The page promotes the full Semrush AI Visibility Toolkit alongside a seven-day trial.

The Ahrefs Free AI Visibility Checker takes any brand name, product name, or competitor name and queries search-backed prompts across ChatGPT, Gemini, Perplexity, Copilot, Google AI Overviews, and Google AI Mode. It requires no sign-up or credit card, and places no limit on the number of brands you check. The output provides a snapshot preview limited to the top 5 topics, top 5 cited domains, and top 5 cited pages. The page links to Ahrefs Brand Radar, which lists pricing at $199 per month for select platforms or $699 per month for all platforms. Prices are as shown on each vendor page in October 2026 and can change.

HubSpot AI Search Grader evaluates brand perception derived from training data across GPT-5.4 mini, Perplexity, and Gemini. It requires your company name, location, industry, and product category. The tool scores brands across five specific dimensions: Sentiment up to 40 points, Presence Quality up to 20 points, Brand Recognition up to 20 points, Share of Voice up to 10 points, and Market Competition up to 10 points. While marketed with no account required, accessing full results requires completing an on-page form. HubSpot points users toward HubSpot AEO at $50 per month.

The Mangools AI Search Grader accepts a brand name and niche description, automatically generates prompts, and measures the share of generated prompts where the brand appears in the top 20 results, plus its average ranking position. The free version checks ChatGPT via GPT-5 Nano, Mistral Small 3.2 24B, and Meta Llama 3.3 70B Instruct without an account. Creating a free account unlocks Claude Haiku 4.5, Google Gemini 2.5 Flash Lite, and DeepSeek V3. The tool generates an AI Search Score from 0 to 100 in under 60 seconds and links to AI Search Watcher.

The GoBIG Systems Free AI Visibility Checker focuses on local service queries, such as roofing in specific cities. Users submit their business name, website, service industry, and city. The tool reports competitor names recommended by ChatGPT, Claude, and Perplexity in 30 to 60 seconds without assigning a numerical score. GoBIG Systems operates as an agency and points users to a free roadmap call.

• Input requirements: Semrush asks for domains; Ahrefs and Mangools take brand names; HubSpot and GoBIG require location and category context.
• Engine reach: Ahrefs tracks six major engines; Semrush tracks four; Mangools includes open-source weights like Llama and Mistral.
• Output data: Semrush and HubSpot provide composite 100-point scores; Ahrefs provides top-5 data tables; GoBIG lists specific local competitors.

On-Site Technical Readiness Checkers

On-site technical readiness checkers inspect page structure, server responses, and bot permissions rather than asking generative models about your brand name. These tools evaluate whether AI scrapers can fetch your text, whether client-side JavaScript obscures critical information, and whether structured data clarifies your content.

The Adobe AI Content Visibility Checker is a free Chrome extension published by Adobe, Inc., updated to version 3.2.1 on October 9, 2026. The extension measures single-page machine-readability by attempting to fetch the page as ChatGPT's crawler would, comparing that view to what a human user sees. It flags content hidden from ChatGPT, Perplexity, and Claude due to client-side rendering. It provides a Citation Readability Score showing the percentage of page text accessible to agents, without requiring an Adobe account.

The Layer3Labs AI Visibility Checker evaluates any single webpage URL with zero registration or email required. It analyzes robots.txt directives, XML sitemaps, and llms.txt files. To verify server firewalls do not block AI user agents, it executes a live fetch using OpenAI's OAI-SearchBot user agent. The output includes a score from 0 to 100 and a letter grade from A to F across six categories: AI crawler access (30 points), readability without JavaScript (15 points), structured data (15 points), answer structure (20 points), trust and freshness (12 points), and discoverability (8 points). The tool displays an 11-crawler permission table, a prioritized fix list, and a Copy Report button. It measures readiness only and cannot see mentions or citations. It checks one URL per run, and its category weights are Layer3Labs' own judgment.

Am I Visible on AI provides a free instant check of a single URL without sign-up or credit card requirements. The tool checks four categories: AI crawler permissions in robots.txt for GPTBot, ClaudeBot, and PerplexityBot; content structure; technical infrastructure such as HTTPS and sitemaps; and schema markup including FAQ and Product structured data. The report assigns an overall score where 85 or above represents excellent readiness, 75 to 84 is good, 65 to 74 is fair, and scores below 65 indicate structural barriers. The vendor notes that the median site scores 77.

The AI Visibility Checker, founded by Benjamin J. Schütz, runs 10 heuristic checks across three pillars: indexability, understandability, and recommendability. It inspects robots.txt access for ChatGPT, Claude, and Gemini, tests for llms.txt files, reviews schema markup, and calculates signal-to-noise ratios. It outputs a score from 0 to 100, grouping results into weak (0 to 39), moderate (40 to 69), and good (70 to 100). The diagnostic is free without rate limits beyond abuse prevention, and the site sells a one-time Premium Fixing Guide for $19.99.

• Crawler permissions: Layer3Labs checks 11 AI user agents; Am I Visible on AI checks three; AI Visibility Checker does not publish its user-agent count.
• Rendering checks: Adobe compares the page a crawler fetches with what a visitor sees; Layer3Labs checks raw HTML text without JavaScript.
• Cost and upgrades: Adobe points to enterprise Adobe Brand Visibility; AI Visibility Checker offers a $19.99 fixing guide; Layer3Labs provides a free GEO checklist.

Limits of Free AI Visibility Checks

Free AI visibility checkers provide diagnostic snapshots rather than automated monitoring systems. For week-over-week tracking, move to a paid tracker; see best AI visibility tools.

Prompt-based free checkers test small, isolated prompt samples. Ahrefs caps free previews at the top 5 results per section, concealing the broader long-tail distribution. HubSpot relies on training data perception across three models rather than live retrieval-augmented generation. Semrush limits free usage to three runs per day, which restricts cross-portfolio auditing. Mangools limits its no-account tier to ChatGPT (GPT-5 Nano), Mistral Small and Llama 3.3, and requires a free account for Claude, Gemini and DeepSeek.

Scores from different checkers cannot be compared directly against one another. A score of 75 on HubSpot measures training-set sentiment across five perception dimensions. A 75 on Semrush is a 0 to 100 AI Visibility Score drawn from answers in ChatGPT, Gemini, AI Overviews and AI Mode. A score on Am I Visible on AI or Layer3Labs reflects crawler access, structure and schema on the page. Each vendor applies proprietary scoring weights and distinct baseline criteria.

On-site checkers evaluate technical prerequisites rather than commercial outcomes. A high score on the Layer3Labs checker or Am I Visible on AI means crawlers can fetch and parse the page. That score does not confirm that ChatGPT or Perplexity will mention or recommend the brand in response to commercial prompts.

• Sample sizes: Free tools show a small sample of prompts and never the full spread of queries in your category.
• Score divergence: Different tools measure completely different technical or semantic variables.
• Causal separation: Clean technical readiness enables bot crawling but does not guarantee citation.

How to Choose by Situation

Local contractors, service providers, and brick-and-mortar operators should run the GoBIG Systems Free AI Visibility Checker. Because it incorporates city and service parameters, it reveals which local competitors ChatGPT and Perplexity recommend in specific geographic markets without forcing you to interpret national brand scores.

Brand marketers and digital agencies needing quick share-of-voice checks should start with the Ahrefs Free AI Visibility Checker. Its zero-sign-up workflow allows you to check competitor brand names without an account. If you need domain-level performance and page-specific citations across Google AI Overviews, run your three daily checks on the Semrush AI Search Visibility Checker. For head-to-head paid differences between these two ecosystems, read our Semrush AI Visibility vs Ahrefs Brand Radar comparison.

PR leads and brand strategists diagnosing reputational positioning should run the HubSpot AI Search Grader. Its sentiment breakdown identifies whether AI models associate your company with positive or negative attributes. Teams tracking open-source models should run the Mangools AI Search Grader to inspect performance across Meta Llama and Mistral Small.

Web developers and technical SEO leads troubleshooting dynamic websites should install the Adobe AI Content Visibility Checker Chrome extension. It pinpoints text lost behind client-side JavaScript rendering. For a whole-page readiness score and fix list, run your core landing pages through the Layer3Labs AI Visibility Checker, Am I Visible on AI or AI Visibility Checker. The Layer3Labs checker also tests 11 AI crawlers in robots.txt and makes an OAI-SearchBot fetch to spot firewall blocks. Create an llms.txt file with our llms.txt generator.

• Local service businesses: Choose GoBIG Systems for geo-targeted competitor recommendations.
• Agencies comparing competitors: Choose Ahrefs for unrestricted brand name checks.
• Domain-level SEO teams: Choose Semrush for top cited page audits.
• PR and brand managers: Choose HubSpot for training-set sentiment scoring.
• Technical developers: Choose Adobe to audit browser rendering and JavaScript gaps.
• Webmasters auditing bot access: Choose Layer3Labs, Am I Visible on AI or AI Visibility Checker for a readiness score and fix list.

The Verdict

No single free AI visibility checker answers every diagnostic question. Prompt-based tools and on-site readiness tools evaluate two separate halves of AI search optimization. Most sites need one tool from each category.

For prompt-based checks without an account, Ahrefs gives a competitor snapshot across six engines. Semrush adds domain-level citations across four engines within three daily checks. For on-site checks, Adobe shows text hidden behind JavaScript, while Layer3Labs, Am I Visible on AI and AI Visibility Checker score crawler access and structure without seeing mentions.

Skip prompt checkers if you only need to know whether crawlers are blocked. Skip on-site checkers if your pages already pass and you need mention counts. Once you need trends over weeks rather than one snapshot, a paid tracker such as Brand Radar, HubSpot AEO or AI Search Watcher is the better fit.