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Every list of “free AI tools for stock research” I’ve read looks like somebody spent twenty minutes on each tool’s pricing page and never logged in. They’re pricing-table reviews dressed up as practitioner guides: “has a free tier” treated as the same thing as “useful at the free tier”, trials counted as free access, and the £2,000-a-month institutional terminals padded in so the list looks comprehensive.
So I did it the other way round. I took each tool to its actual free tier, ran a real research task on it, and wrote down what came back. Some of it was good. Some of it quietly suggested I go and pay for something else. Nobody uses one tool for everything, so the question isn’t which AI is best overall for stock research. It’s which one belongs at which stage of a session.
It's a verdict per task here, not per tool. Used together, these seven cover most of what a retail investor needs before they place a trade, and they cost nothing.
Free tiers move. Prompt caps, context limits and how many years of data you get all shift as these companies tune what they give away. The numbers here were re-checked in June 2026; where a figure is the kind that drifts, I’ve said so in the entry, and the pricing page is always the final word.
Seven free tiers, and the one job each is good at
The best free AI tools for stock research in 2026, in the order they belong in a session:
- Perplexity Finance best free first pass on a US name (stock page, earnings hub, plain-English screener).
- Fiscal.ai best free source for verified fundamentals (numbers sourced from a professional data feed, not web summaries).
- Gemini best free tool for reading a document, within its limits (it's got the most generous free file handling, but a tight context window means very long filings need feeding in sections).
- Quiver Quantitative best free source for the data that isn't in the filings (congressional trades, insider activity, lobbying spend).
- StockAnalysis.com best free way to check a number an AI gave you (no login, no prompt limit, global coverage).
- Claude best free tool for arguing against your own view (most controllable, says plainly when it isn't sure).
- Koyfin best free terminal for companies listed outside the US (UK and European stocks Perplexity ignores).
No single one does the whole job, and no free tool sees a live options chain. Here’s the detail below: what each free tier actually includes, and where it quietly pushes you to pay.
A seven-day trial is not a free tool
Permanent free access. That's the whole test. Several of the tools below have paid tiers that are better, and that's fine.
A 7-day trial. Any product whose "free" experience is a clock counting down to a paywall doesn't appear here.
Three times this year I’ve gone to use a “free” service and found the price tag stapled just inside the door, so this list holds a hard line. The question this post answers is what you can do without paying.
Perplexity Finance: first pass on a new name
Use it when: You’ve heard about a company and you want a structured briefing (financials, recent earnings, what analysts are saying) before you commit time to deeper research.
Why it earns its place: The free tier of Perplexity Finance is the single most capable opening-phase research tool on this list for US-listed companies. There’s no prompt-writing skill required and no setup. For the first thirty minutes on a new US name, nothing else at free tier comes close.
- Live US stock pages.
- Earnings hub with documents (transcripts, filings).
- Plain-English screener for US and Indian stocks. A screener filters thousands of stocks down to the few that match what you ask for.
- Price and chart comparisons.
- Consensus analyst estimates, meaning the average of what analysts expect.
- Throttled Deep Research sessions.
I ran the same earnings query on two stocks I follow, BMNR (a smaller US company) and META, and got two completely different tools.
The Earnings Transcript tab showed "Loading…" and never populated. The query came back with fifteen secondary sources: Yahoo Finance summaries, news aggregator paraphrases. No named analysts, no direct quotes from the calls.
Perplexity signed off by suggesting I try Seeking Alpha Premium for transcript access.
The same query returned named analyst Q&A from Morgan Stanley, Goldman Sachs and JPMorgan, with specific Zuckerberg quotes.
On top of that, a cross-call synthesis identifying a recurring evasion pattern in how management answered questions about margin trajectory.
Top: BMNR. Bottom: META. Same tool, same prompt.
That’s two completely different research experiences from one tool. The structured Finance tab depends entirely on whether Quartr, the company that supplies Perplexity’s transcripts, has already processed that company. For the larger ones it has. For smaller names, and that includes plenty of US ones, not just the UK minnows, you’re back to a plain web-search summary. That’s where the quality quietly drops: a web-search answer is only as good as whatever source happened to rank, and turning search on moves the error rather than removing it.
Where it falls short. If your watchlist skews to smaller names, Perplexity Finance at free tier is excellent for the household names and approximately useless for everything else.
And if earnings calls are the specific job you’d be hiring these tools for, I ran that comparison separately: the best AI tools for earnings analysis, tested on a real quarter’s transcripts.
Fiscal.ai (formerly FinChat): verified fundamentals
Use it when: You want to dig into the financials of a specific company (how its sales and profit margins have moved over the years) without reading the annual report (the 10-K) yourself, and without an AI inventing the numbers.
Why it earns its place: Fiscal.ai, the tool that used to be called FinChat, renamed mid-2025, pulls its data from S&P Market Intelligence, one of the feeds that also supplies Bloomberg, rather than scraping it from web summaries. When it cites a revenue figure, that’s a citation you can actually check. The distinction matters: ask a general-purpose AI for a revenue number and it’ll happily produce a plausible-looking one that’s wrong by ten per cent. Fiscal.ai sources its numbers and shows you where they came from.
- 10 AI Copilot prompts per month.
- Global stock coverage, not US-only.
- Several years of annual financial data and a handful of quarters of detail.
- Limited earnings call access.
- Financial dashboards and charts.
Fiscal.ai has tweaked the exact depth of that free tier more than once since the FinChat rebrand, so check the current numbers on the pricing page before you lean on them. At the time of testing there was also an option to connect it to your broker, with a long list of supported brokers, which is a nice touch for a free tier if it’s survived the rebrand.
The 10-prompt monthly limit sounds generous until you use it in anger. I watched mine drain inside a single sitting.
Two companies a month is what the free tier covers before you start rationing. The data depth is the second constraint: a few years of annual figures is enough to draw a trend line, but the short run of quarterly detail on the free tier isn’t enough to see a full cycle in a business that’s seasonal, or that swings with the economy, or that’s only just floated on the stock market.
Where it falls short. Ten prompts go faster than you expect. Run one thorough multi-part session on a company and you've spent a third of your monthly allowance.
Gemini: document-heavy analysis
Use it when: You’ve got a long PDF (annual report, earnings release, risk factors section) and you want to dig into it directly rather than skim it.
Why it earns its place: Gemini’s free tier handles file uploads better than any other free general-purpose AI. ChatGPT free can’t really take a full annual report; Claude free has tighter document limits. Gemini’s free tier accepts the upload and answers questions against the actual text, plus five Deep Research reports a month, the longer dossier-style answers, which ChatGPT keeps behind its paywall.
Here’s the honest catch, current as of June 2026.
That’s enough for an earnings release or a single section, but a full annual report (the 10-K, a US company’s detailed yearly filing) runs several times longer. It’s the difference between “upload it and ask anything” and “upload a section and ask about that section.” On prompt limits, Google doesn’t publish a fixed daily count for the free app: you get a standard allowance that resets every few hours, and once you’ve used up the most capable model you’re dropped to a lighter one for the rest of that window. Both the window and the allowance move, so treat them as the state of play this month, not a fixture.
- File upload, up to 10 files a prompt.
- A context window of roughly 32,000 tokens, about fifty pages.
- A standard prompt allowance on a rolling reset that drops you to a lighter model once it's spent.
- 5 Deep Research reports a month.
- Web access.
Gemini summarises well and challenges poorly. Ask it to “analyse this annual report” and you’ll get a polished version of how management framed the year. The fix is in the prompt: I stopped asking Gemini to assess and started asking it to find.
"List every risk factor in section 1A that management spends less than a sentence on"
"Find every place the words 'one-off' or 'non-recurring' appear and quote the surrounding paragraph"
Either of those gets you something specific to push back on, rather than a tidied-up retelling of the company’s own story.
The other failure mode is confident-sounding numerical error: Gemini will sometimes paraphrase a financial figure that’s close enough to look right and wrong enough to mislead. It’s one of the named ways AI gets a number wrong, and the most expensive on a research task. I check every number it gives me against the source document.
It states the wrong number with exactly the same composure as the right one.
Where it falls short. Ask Gemini for a balanced view and you'll get the company's version of balance. Either the prompt turns adversarial or you accept the marketing.
Quiver Quantitative: alternative data signals
Use it when: You want signals that don’t come from the company’s own filings: what Congress members are trading, what insiders are doing, what hedge funds are building or selling, where lobbying money is going.
Why it earns its place: Quiver Quantitative’s free tier includes the actual alternative datasets that hedge funds pay for. This isn’t AI inference from news. It’s parsed from public disclosures. No equivalent free source exists for this category of data, and that’s the entire reason it sits on the list.
- Congressional trading tracker.
- Insider transaction data.
- Government contract awards.
- Lobbying spend.
- Hedge fund and institutional holdings.
- ETF flows.
- Backtesting and real-time alerts are paid.
The raw disclosure data. Who bought, who sold, what was filed and when, straight from the public record rather than inferred from news.
The reading of it. The first thing I do with any entry is check the disclosure date against the trade date: a congressional buy that showed up in March might be a January trade, because the law gives members 30 to 45 days to report, and Senate disclosures often lag further still.
It supplies the signal; you do the interpretation. Insider selling has a dozen innocent explanations: a pre-scheduled selling plan set up months earlier, tax owed on newly granted shares, a divorce. A jump in lobbying spend can be defensive or offensive.
The most-watched page in recent years has probably been Nancy Pelosi’s trading history. Following her trades became a retail investor trend. She consistently outperformed the market, and the theory that she had access to material non-public information through her Congressional position gained enough traction to get mainstream media coverage. Whether you believe that or not, the STOCK Act data is public, and that’s where you’d look.
Where it falls short. The free tier has no alerts and no backtesting. You find out about a congressional trade when you visit the site, not when it happens. If you want to act on these signals rather than just see them, you'll need a paid plan.
StockAnalysis.com: the verification layer
Use it when: You want to check whether the financial figure an AI just gave you is correct, without an account, without a prompt limit, without another AI in the middle.
Why it earns its place: StockAnalysis.com isn’t an AI tool in the generative sense. It’s a clean fundamentals database with AI-enhanced screening, free forever, with no login required. It earns its place on a list of AI research tools because it solves the problem that AI research tools create: you need somewhere to verify what the AI just told you, and most of the obvious options (Yahoo Finance, broker apps) are either ad-cluttered or thin on international coverage.
- Full financial statements, ratios and historical data.
- No-login stock screener.
- IPO calendar.
- Market news digest.
- ETF data.
- Ad-supported, free forever.
The AI component is on the screening and data-presentation side, not a chat box. You can’t paste in a company name and ask “why is the operating margin shrinking” (why each pound of sales is turning into less profit), you’ve got to read the data yourself. For this job, that’s a feature. The tool’s role here is to be hard to get wrong, not to do the thinking.
That’s the tab I keep open in the background. When another AI tells me Company X’s revenue grew 18% last year, StockAnalysis is two clicks away and it hasn’t got an opinion to defend. It’s also the step most people skip. A sourced AI answer feels checked because it’s got a link attached, but the link doesn’t always say what the answer claims, which is a trap worth seeing for yourself.
Where it falls short. It gives you the data, not the analysis. You're using it to verify outputs, not generate them, and you need both, from different tools.
Claude: structured adversarial reasoning
Use it when: You’ve got a view on a stock and you want to stress-test it. Bear case, what-would-change-my-mind, the questions you haven’t asked.
Why it earns its place: Claude’s free tier includes web search, but every search eats into your usage allowance and the results come back as a list of pages, not the structured financial data you’d get from Perplexity Finance. For the specific job of arguing against your own view, though, Claude is the most controllable free tool available. It handles multi-part structured prompts reliably and tends towards saying plainly when it isn’t sure, rather than the false-confident summarising Gemini drifts into. If you want the AI to push back, it’s the one that will.
- Claude Sonnet 4.6, the free default since early 2026.
- Web search and limited file upload.
- Both count against a rolling usage cap that refills every five hours rather than once a day. Anthropic switched to that window in April 2026.
Here’s where the Prompt Stack earns its keep, the four-part prompt I run before any trade. The free Claude tier on its own is a general assistant. The same tier with that structure turns into something that argues back properly.
- SCOPE. Work only from the figures you paste in, and say so rather than guess if a number's missing.
- FILTER. Here are the observable facts.
- RISK. Name the timing, the downside, and what would invalidate the view.
- VERDICT. One action, with a confidence level.
The six Claude prompts I run, with the real outputs they produced on MSFT, META and NVDA, show what that structure gets you in practice. Paste in your view on the stock in three sentences, paste in the real financials from StockAnalysis or Fiscal.ai, and ask Claude to argue the bear case (the case for selling) against your own framing. You’ll get something usable. Ask the same question without the structure and you’ll get a five-paragraph “on the one hand, on the other hand” essay.
The catch is that Claude doesn’t know what you don’t tell it. Paste in inference instead of numbers and you’ll get inference back, dressed up as analysis.
Where it falls short. Claude's free tier is a reasoning engine, not a research engine. You've got to bring all the facts; it applies the logic to them.
Koyfin: data terminal for international coverage
Use it when: You want a Bloomberg-style data terminal (the kind of dense single screen professionals pay thousands a year for, with charts, company metrics, the wider economic backdrop, and custom watchlists), and your watchlist isn’t all US household names.
Why it earns its place: Koyfin does the thing Perplexity Finance can’t: it covers companies listed outside the US. UK and European stocks have proper data pages, with fundamentals, charts, and screening that work the same way they do for US names. If anything in your portfolio sits outside the S&P 500 (the index of the 500 biggest US companies), that’s the difference between a working tool and one that pretends Europe doesn’t exist.
- 2 years of historical financials.
- Stock and ETF data, plus fundamental metrics and charting.
- 2 watchlists and 2 custom screens.
- Limited macro dashboards.
The honest limit is data depth.
Koyfin knows this, which is why they pitch the free tier as a demonstration, not a working environment. Paid starts around $39/month, which is reasonable for what you get if you’re researching more than a handful of names. The 2 watchlists and 2 screens cap is the other constraint. For someone tracking five sectors and a dozen names, the free tier gets cramped fast.
Where it falls short. At free, Koyfin shows you what the platform can do, not what you can do with it. Worth noting too: I hit network errors trying to create a free account, which suggests the signup experience isn't well-maintained. Not a great first impression for a tool positioning its free tier as a demo.
Where the list stops
The early-to-middle stages. First pass, fundamentals, document analysis, alternative data, verification, sceptical reasoning, data terminal.
Live options chains, UK depth, alerts. There's no genuinely free tier for options data at all. Real-time alerts are paid everywhere.
Live options chain data has no genuinely free tier; broker apps are still the answer there. Structured coverage of AIM (London’s market for smaller, younger companies) and the broader UK market is patchy across the entire list. Perplexity Finance ignores it, Koyfin partially covers it, Fiscal.ai does best but burns prompts fast.
The pre-trade reasoning stage (the hour between deciding a stock is interesting and placing the order) is where this list ends. Five questions to ask AI before buying any stock picks up there, with the prompts I run before any trade goes on.
Seven free tools, in the order they belong in a research session. Use this as a session template, start at the top, work down.
- Perplexity Finance - first pass on a new name: live stock page, earnings hub, plain-English screener (filters thousands of stocks to the ones that match what you ask). Limit: works well on US household names; smaller companies often return web-search summaries instead of structured data.
- Fiscal.ai - verified fundamentals: revenue, margins, cash generation, sourced from S&P Market Intelligence rather than web summaries, so you can check where the numbers came from. Limit: 10 AI prompts per month, and a thorough session on one company can spend three or four of them.
- Gemini - document analysis: upload an annual report (the 10-K, the detailed yearly filing companies must publish) or earnings release and ask specific questions against the actual text. Limit: a roughly 32,000-token free context window means a long filing has to be fed in sections, not held whole; it also summarises in the company's favour unless you make the prompt adversarial, so check every number against the source.
- Quiver Quantitative - alternative signals: congressional trades, insider transactions, government contract awards, lobbying spend, parsed from public disclosures, not inferred from news. Limit: no free alerts or backtesting; you see the signal when you visit, not when it happens.
- StockAnalysis.com - verification layer: full financial statements, global coverage, no login, no prompt limit. Use it to check whether the number an AI just gave you is correct. Limit: gives you the data, not the analysis, you read it yourself.
- Claude - structured adversarial reasoning: paste in your view on the stock and the real figures from StockAnalysis or Fiscal.ai, then ask Claude to argue the bear case (the case against buying) against your own framing. The Prompt Stack structure (SCOPE, FILTER, RISK, VERDICT) makes the response substantially more useful than an unstructured question. Limit: a reasoning engine, not a research engine; bring the facts, it applies the logic.
- Koyfin - data terminal: Bloomberg-style dashboard with charts, fundamentals, and screening for companies listed outside the US, UK and European stocks included, which Perplexity Finance largely ignores. Limit: two years of historical data at free tier, which is a snapshot rather than a pattern; two watchlists and two custom screens cap how much you can track.
Five that didn’t make it, and why
- ChatGPT free. The exact message allowance keeps moving, and OpenAI has changed it more than once in 2026, but the shape holds: it runs out mid-session, and Deep Research stays behind the paywall. Not enough for one thorough research pass. It's on most other lists because the brand is familiar, not because the free tier is useful.
- Danelfin. The free tier is the "top 10 stocks to buy" newsletter, a marketing funnel for the paid scoring product. It delivers Danelfin's conclusions, not the data to form your own. That's a stock-picker subscription, not a research tool.
- Zen Ratings. WallStreetZen's own product, recommended at the top of WallStreetZen's own "best AI tools" lists. The free tier is described by the parent site as "limited stock research" without specifying what that limit is. Conflict of interest aside, "limited" without a definition fails the free-tier-honesty test this post is built around.
- Prospero.ai. Claims 27% better returns than the S&P 500. Doesn't publish audited results or methodology. Delivers signals rather than enabling research.
- Robinhood Cortex Digests. The only AI feature built into a UK broker, and the list's cautionary tale. I audited it line by line in May; by June it had vanished from my account, mobile app included. The full audit is now a record of what it did while it lasted. Broker AI is the one tool category where somebody else holds the off switch.
That is the whole selection rule. The seven above were picked because they help you do your own research, not because they promise to do it for you.
For a direct head-to-head on which of these tools handles which research task best, the full comparison runs the same five prompts across ChatGPT, Claude, Perplexity, and Gemini on the same day.
The short version
What worked: Used in sequence (Perplexity for the first pass, Fiscal.ai for verified fundamentals, Gemini for documents, Quiver for alternative data, StockAnalysis to check the numbers, Claude to stress-test the view, Koyfin for companies listed outside the US), the seven free tiers cover most of a real research session without paying for anything.
What didn’t: No free tool gives you live options data. Perplexity Finance works beautifully on US household names and falls apart on smaller ones. Fiscal.ai’s 10-prompt monthly cap goes faster than you expect. Koyfin at two years of history is a demo, not a working environment.
Bottom line: Tested at the free tier on real names, with the gaps stated. Coverage thins out on smaller companies and non-US stocks, and that’s the caveat to hold on to. The tools are free; the judgement still has to be yours.
These are the seven I use. Once you’ve hit the free-tier limits on two or three of them, you’ll know which one is worth paying for, and by then you’ll have run enough real sessions to make that call yourself.
And if you’re wondering how far any of these AI answers can be trusted in the first place, that question has its own page: the State of AI Reliability report grades every checkable answer this site has collected against the primary source, and keeps the score where you can audit it.
Ben tests how far you can trust the main AI assistants, and publishes exactly where they get things wrong. Every post here is a first-hand test with the receipts, including the times a tool simply wasn’t worth the trust. About Ben →
The site tests how far you can trust the main AI assistants, on real decisions. Start with the Prompt Stack for the four-stage framework, free and ungated, or the Bluff Filter for the paste-ready version with a real before and after.