Everything below comes from each tool's own page, read on October 8, 2026. We haven't run them yet: our next test puts the same brand through every checker on the same day and compares the answers. Until then, this page tells you what each one says it does, which is already enough to rule some out.
The three kinds of free checker
- Live prompt runs. The tool sends a set of questions to AI assistants now and reads the answers. Closest to what your customers see, but a single run is a snapshot: AI answers change from one run to the next. Frase, Backlinko, Mangools, Birdeye and Honeyb work this way.
- Database lookups. The tool searches answers it has already collected at scale. Fast and broad, but the questions are the vendor's, not yours. Ahrefs and Semrush work this way.
- Graders with no live search. HubSpot asks AI models what they know about your brand "based on its training data". Arobis and Am I Visible on AI check whether your site is readable by AI crawlers. Useful, but neither tells you whether you're mentioned in real answers.
The comparison
| Checker | You enter | Engines (as claimed) | Sign-up | Limit | Kind |
|---|---|---|---|---|---|
| Ahrefs | Brand name | ChatGPT, Gemini, Perplexity, Copilot, AI Overviews, AI Mode | None | None stated; top 5 per section | Database |
| Semrush | Domain | Page says four, but its FAQ lists Gemini and AI Mode as "coming soon" | None | 3 a day | Database |
| Backlinko (owned by Semrush) | Company, site, category, one competitor | ChatGPT, Perplexity, Gemini | None to start | 1 a day | Live (150 queries) |
| Frase | Domain or URL | ChatGPT free; Perplexity, Gemini after email | Email for 2 of 3 engines | 3 phrases per check | Live |
| Mangools | Brand + niche | Small API models: GPT-5 Nano, Mistral, Llama free; more with a free account | Free account for all models | "Limited", no number | Live (API models) |
| HubSpot AI Search Grader | Company, location, products, industry | GPT-5.4 mini, Perplexity, Gemini | Short form for the full report | One-time | No live search (training data) |
| Amplitude | Company name | ChatGPT, AI Overview | Not confirmed | "Limited" | Not stated |
| Searchable | Website | ChatGPT, Google, Perplexity | Likely email delivery | Not stated | Not stated |
| SEO Review Tools | Brand or URL, products, competitors | Gemini, ChatGPT, Perplexity | Credits meter shown | Not stated | Not stated |
| Birdeye | Business, website, location | ChatGPT only (free) | Consent to contact | One location | Live |
| Honeyb | Not stated | One engine free | None for one engine | One engine | Live |
| Arobis | Domain | n/a (checks your site) | None | ~25-second scan | Site readiness |
| Am I Visible on AI | Website | n/a (checks your site) | Not stated | Not stated | Site readiness |
Things the vendor pages admit
- Answers change between runs. Frase calls its result a snapshot because AI engines rewrite answers constantly. Semrush's FAQ warns you may see different answers when you test prompts yourself.
- Small models aren't the apps your customers use. Mangools names GPT-5 Nano, Claude Haiku 4.5 and Gemini 2.5 Flash Lite; HubSpot names GPT-5.4 mini. Those are cheaper API models, not what someone sees in the ChatGPT or Gemini app.
- Semrush contradicts itself. The same page lists four engines in its body text and two (with two "coming soon") in its FAQ.
Which one should you use?
- Just want to know if AI mentions you at all: Ahrefs. Brand name in, no sign-up, six engines.
- Want live answers about your category: Backlinko (one free run a day, 150 queries) or Frase (three phrases, ChatGPT free).
- Want to fix your site for AI crawlers: Arobis, which checks robots.txt and structured data rather than mentions.
- Want to track change over time: no free checker does that. Look at the cheapest paid trackers instead.
Every free checker leads to a paid product: Ahrefs to Brand Radar, Semrush and Backlinko to Semrush's AI Visibility Toolkit, HubSpot to HubSpot AEO, Frase to its own platform. That's fine, but it's why none of them will tell you a competitor's tool would serve you better. Prices for those paid tools are in our price index.
Source notes: each tool's own page, read Oct 8, 2026 in a fresh browser with no account. Engines and limits are as each vendor states them; we'll confirm by running each one.