Best Free Answer Engine Monitoring Tools (2026): Verified Limits

The best free answer engine monitoring tools in 2026 come in five shapes, and only one of them is free forever: one-shot checkers such as HubSpot's AI Search Grader. Everything else is a capped free tier, a trial with a clock on it, an open-source project you host and pay model fees for, or a spreadsheet you fill in by hand.

Below is what each option allowed on 2026-10-21 without paying: sign-up, card, runs and history. Where a vendor page was silent, we wrote "not verified". Kairosy sits in the trial group: 7 days, no card, then paid. At the end there is a weekly log you can copy for free brand reputation monitoring by hand.

Which Free Answer Engine Monitoring Tool Should You Try First? (TL;DR by Free Type)

• Forever free, one-shot: HubSpot AI Search Grader. No account, no cost, one report on how ChatGPT, Perplexity and Gemini describe your brand.
• Free tier you keep: a Semrush free account. One demo project and 10 reports a day, AI Visibility features in limited form, no card.
• Time-limited trial: Kairosy. 7 days, no card, 50 tracked prompts a day on 2 project slots across 4 of its 6 engines, then a paid plan from $29 a month.
• Open source: Limelit Open. Apache-2.0, one Go binary with SQLite, bring your own model keys, exports JSON or CSV.
• Manual: the engines' own free tiers plus the weekly log template below. Zero dollars, real hours.

Want to know whether engines name you at all? Run a one-shot checker today. Need change over time? Only open source and your own sheet keep history for free.

Free Answer Engine Monitoring Tools Compared: Quota, Engines, Cadence, History and Export

This is the sign-up log merged with the comparison columns. Every cell was read from the vendor's own page on 2026-10-21. "Not verified" means the page did not say.

Tool	Free type	Sign-up / card	What you can run free	Engines	Cadence and history	Export
HubSpot AI Search Grader	Forever free	Four-field form, no account, no card	One-time check	ChatGPT, Perplexity, Gemini	Snapshot, no history shown	None shown
Ahrefs AI Visibility Checker	Forever free	No signup, no card	Unlimited brands, top 5 results per section	ChatGPT, Gemini, Perplexity, Copilot, AI Overviews, AI Mode	Snapshot only	None shown
Backlinko AI Brand Visibility Checker	Forever free	Not stated	150 live queries per run	ChatGPT, Perplexity, Gemini	History not stated	Not stated
Semrush free account	Free tier	Account, no card	1 demo project, 10 reports a day	Paid: ChatGPT, Perplexity, Gemini and more	Daily prompt tracking is paid (Starter, $199/mo)	Paid
LLMrefs free account	Free tier	Account, no card	Limits not published	Paid: 10+ engines incl. ChatGPT, Claude, DeepSeek	Paid: at least weekly updates	Paid: CSV, API
Kairosy	7-day trial	Account, no card	50 tracked prompts a day, 2 slots	4 of 6: ChatGPT, Gemini, Claude, Perplexity, DeepSeek, Doubao	Prompts daily, deep rescan weekly, past reports readable after trial	Not verified
Otterly.AI	7-day trial	No card	50 prompts during trial	ChatGPT, AI Overviews, Perplexity, Copilot	Daily on paid plans	Not verified
Rankscale	7-day Pro trial	Card: not shown on pricing page	Pro credits, 0.25 credit per engine per prompt	ChatGPT, Gemini, Perplexity, Claude	Not verified	Not verified
Trakkr	14-day trial	Card required, $100/mo after day 14	50 prompts per brand	8 models incl. ChatGPT, Claude, Gemini, Perplexity, DeepSeek	Daily, 1 year history on Growth	CSV
Limelit Open	Open source, Apache-2.0	No account, your own API keys	Unlimited, you pay model fees	ChatGPT, Claude, Perplexity, Gemini, AI Overviews, AI Mode, Copilot	Daily or hourly runs, SQLite history	JSON or CSV
ai-visibility-tracker	Open source, MIT	Vercel account, AI Gateway balance	Unlimited, list-price model fees	ChatGPT, Perplexity, Gemini, Claude, Grok	Daily and weekly cron, history by period	CSV

What Are the Best Free Answer Engine Monitoring Tools in 2026, by Free Type?

Free AI visibility monitoring means something different in each of the five groups, so each entry says what "free" buys and where it stops.

Forever-free one-shot checkers

HubSpot AI Search Grader. The page calls it "a free, one-time check" with "no cost to run an AI Search Grader analysis." The form asks for company, location, product and industry, and no email. The report scores five dimensions out of 100: sentiment 40 points, presence quality 20, brand recognition 20, share of voice 10, market competition 10, cross-checked across GPT-5.4 mini, Perplexity and Gemini. There is no history. Ongoing monitoring is HubSpot's paid AEO product at $50 a month, per the same page.

Ahrefs AI Visibility Checker. "No signup, no credit card, no limit on how many brands you can check." It reports total mentions, mentions per platform, and the top 5 topics, cited domains and cited pages across six platforms including Copilot and Google AI Mode. It is explicitly "a limited preview (top 5 results per section)", shows no sentiment and keeps nothing. Full data is paid Brand Radar, where custom prompt tracking "starts at $50/mo".

Backlinko AI Brand Visibility Checker. It "runs 150 live queries about your category" on ChatGPT, Perplexity and Gemini and scores presence, position, citation, sentiment and confidence. Its sentiment question is literally "Is the mention positive or neutral?", so expect no negative-theme breakdown. Sign-up and history are not stated on the page.

Free tiers you can keep

Semrush free account. The pricing page lists a free tier with 1 demo project, "10 reports per day across all vital tools" and "No credit card required". AI Visibility features are included in limited form, but daily prompt tracking starts on Starter at $199 a month (50 prompts a day). Card terms for its separate seven-day paid trial are not shown there.

LLMrefs free account. "Create Free Account" and "No credit card required" are on the page, but the free account's prompt limit is not published anywhere official. Third-party reviews report one keyword, which we could not verify. The paid All in One plan is $79 a month on a limited-time offer for 500 prompts, updated "at least once per week", with CSV export, API access and its own 7-day trial without a card.

Time-limited trials: no card versus card

Kairosy. The trial is 7 days with no card. You get 50 tracked prompts a day on 2 project slots, choose 4 of 6 engines (ChatGPT, Gemini, Claude, Perplexity, DeepSeek, Doubao), and every answer is stored in full with its cited sources, a sentiment label, extracted negative narratives and a fix strategy. When the 7 days end your reports stay readable, but new scans need Basic at $29, Pro at $99 or Growth at $399 a month. Prompts re-run daily, the deep rescan runs weekly, and changes arrive in a weekly email rather than the moment an answer moves.

Otterly.AI. The help center states "7 day free trial; no credit card required" with 50 prompts during the trial. Paid plans start at Lite, $29 a month for 15 prompts on ChatGPT, Google AI Overviews, Perplexity and Copilot, tracked daily.

Rankscale. "Try Pro free for 7 days." The pricing page does not say whether a card is needed. Pro is $99 a month for 1,200 credits, and each engine query "costs a fraction of a credit (typically 0.25 credits per engine per prompt)". There is no free plan; the cheapest tier is Essentials at $17 a month, yearly only.

Trakkr. "14-day free trial" and, in the same FAQ, "Card required for the trial." If you do not cancel, "you'll be charged $100/mo after 14 days." Growth covers 50 prompts per brand on 8 models with daily runs, one year of history and CSV export. That card is why a trial is never "free forever".

Open-source trackers you host

Limelit Open. Apache-2.0, "One Go binary, SQLite, MCP-first", and "bring your own keys" for the model providers. It tracks ChatGPT, Claude, Perplexity, Gemini, Google AI Overview, AI Mode and Copilot, runs daily or hourly under a runs_per_day ceiling, stores every answer locally ("Nothing leaves the box except the calls to the engines") and exports "JSON or CSV of everything".

ai-visibility-tracker. MIT, "Deploy with Vercel in five minutes", one AI Gateway key for ChatGPT, Perplexity, Gemini, Claude and Grok. It stores "the answer text, the sources the platform returned and the searches it ran verbatim", runs a daily cron at 06:00 UTC and exports CSV. The README is honest about cost: "You pay the model providers through the gateway at list price", with the default trio at "cents per check".

The manual method

ChatGPT, Perplexity, Gemini, Claude and DeepSeek all offer free tiers you can query by hand. The cost is time and discipline: the same prompt wording every week, a fresh chat for every run, and the full answer plus every cited link pasted into the log before you read it. Pick prompts the way the measurement protocol describes and keep the set fixed, because a changed prompt is a new baseline, not a trend.

What Can Free Brand Sentiment Monitoring and Accuracy Checks Actually Tell You?

Free brand sentiment monitoring gives you a label on one run. HubSpot's grader weights sentiment at 40 of 100 points, Backlinko's asks "positive or neutral", and neither hands you the full answer text behind the label. You cannot audit a sentiment score whose source you cannot read.

The second limit is that engines disagree. Kairosy's public scan of Plausible scores the brand 67/100 overall, "At risk", with ChatGPT at 81 and Claude at 44, while Perplexity steers buyers to PostHog, Umami, Fathom and Matomo. A one-engine checker would report one of those numbers and call it "AI sentiment". Why LLMs disagree on sentiment explains the gap.

Accuracy is the check free tools skip. Whether an answer gets your pricing, plan names or refund policy right is something only a person reading the full text can judge, which is why the log below has a "factual error" column. The open-source trackers store the verbatim answer so you can do that reading, and a Kairosy trial shows each engine's full answer with its cited sources, which is where most wrong claims trace back to.

Is free social media sentiment monitoring the same as free AI answer monitoring?

No, and this is the most common mix-up in "free brand monitoring" lists. Talkwalker Alerts is free and watches "news platforms, blogs, forums, websites, and even Twitter (X)". Google Alerts emails you "when new results for a topic show up in Google Search". Both monitor published pages. Neither asks an AI engine a question or records what it answered. Use them to watch the review sites and forums that feed the engines, not as a substitute for answer monitoring.

Free page-readiness checks are a third thing again

Kairosy's free tools such as /tools/llms-txt-validator are "unlimited single checks, no signup needed", grading whether AI crawlers can read your pages with an A to F grade and issues ranked by severity. That tells you whether an engine can read you, not what it says about you. Keep the two questions in separate columns.

How Do You Keep a Free Weekly Monitoring Log by Hand?

Copy the table below into a sheet. The rows are example values for a fictional brand, Northwind Analytics, not measured results. Ten prompts across three engines is 30 runs a week, roughly an hour of pasting.

Week	Prompt	Engine	Mentioned?	Position	Sentiment	Rivals named	Sources cited	Factual error?	Change vs last week
W1 (example)	best privacy-first web analytics	ChatGPT	Yes	2 of 5	Positive	Acme Metrics, Fathom	northwind.example/pricing, g2.com	No	Baseline
W1 (example)	best privacy-first web analytics	Perplexity	No	-	-	Acme Metrics, Matomo, Umami	reddit.com, producthunt.com	-	Baseline
W2 (example)	best privacy-first web analytics	ChatGPT	Yes	3 of 5	Neutral	Acme Metrics, Fathom, Matomo	g2.com, northwind.example/blog	Yes: says no free plan	Dropped one place, new rival

Three rules keep the log honest. Save the full answer before you score it, so a reviewer can disagree with your label. Count a rival only when the engine names it unprompted in an unbranded question. And record "not mentioned" as a row, because that empty row is the visibility number you are tracking. With those rules, a sheet is one of the best free answer engine monitoring tools you will own, and the only one with no vendor clock.

Best Free Answer Engine Monitoring Tools FAQs

Is there a free answer engine monitoring tool that keeps history?

Among hosted products, no. The forever-free checkers are snapshots and the free tiers reserve history for paid plans. Limelit Open and ai-visibility-tracker keep every answer in their own database, but you pay the model providers for each run.

Does Kairosy have a free plan?

No. Kairosy offers a 7-day trial without a card, with 50 tracked prompts a day on 2 slots. After that a free account can read its past reports but cannot scan, and paid plans start at $29 a month. The checkers under /tools are free without sign-up, but they test page readiness, not answers.

Can I monitor brand sentiment for free?

You can get a one-run sentiment label free from HubSpot or Backlinko, and you can read answers yourself and label them in the weekly log. Ongoing sentiment with stored answers means an open-source tracker with your own API spend, or a paid plan after a trial.

Is a free trial the same as a free plan?

No. Trakkr's trial takes a card and bills $100 a month on day 15 unless you cancel. Kairosy, Otterly and LLMrefs trials take no card, so they cannot charge you, but they still end. Only the one-shot checkers, the capped free accounts and the open-source route run with no clock.

What does the open-source route really cost?

The software is free under Apache-2.0 or MIT. The runs are not: ai-visibility-tracker's README says you pay the providers "at list price" through the gateway and that its default trio costs "cents per check". Add hosting and upkeep on top.