Best free AI tools for stock research (2026)

Every existing list of “free AI tools for stock research” reads like it was written by someone who spent twenty minutes on each tool’s pricing page and never logged in. The pieces are 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, the £2,000-a-month institutional terminals padded in to look comprehensive.

This post does something different. 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. The verdict is per task, not per tool. No one uses one tool for everything. The question isn’t which AI is best overall for stock research, but which one belongs at which stage of a research session.

The list is sequenced in that order. First pass on a new name, then verified fundamentals, then document analysis, then alternative data, then a verification layer, then sceptical reasoning, then the data terminal. Used together, these seven cover most of what a retail investor needs before they place a trade, and they cost nothing.

The seven: Perplexity Finance, Fiscal.ai (formerly FinChat), Gemini, Quiver Quantitative, StockAnalysis.com, Claude, and Koyfin.

The short answer

The best free AI tools for stock research in 2026, one job each:

• 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 has the most generous free file handling, but a tight context window means very long filings need to be fed 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. The detail (what each free tier actually includes, and where it quietly pushes you to pay) is below.

One rule before the list

Free tier means permanent free access. A 7-day trial is not a free tool, and any product whose “free” experience is a clock counting down to a paywall does not 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. Several of the tools below have paid tiers that are better; the question this post answers is what you can do without paying.

One more note before the list: 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.

Perplexity Finance: first pass on a new name

Use it when: You’ve heard about a company and want a structured briefing (financials, recent earnings, what analysts are saying) before committing 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. Live stock pages, an earnings hub with sourced transcripts and filings, a screener you drive in plain English (a screener filters thousands of stocks down to the few that match what you ask for), price and chart comparisons, the average of what analysts expect. No prompt-writing skill required, no setup. For the first thirty minutes on a new US name, nothing else at free tier comes close.

What the free tier actually includes: Live US stock pages, earnings hub with documents (transcripts, filings), plain-English screener for US and Indian stocks, price and chart comparisons, consensus analyst estimates, 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.

On BMNR, the Earnings Transcript tab showed “Loading…” and never populated. The query returned fifteen secondary sources: Yahoo Finance summaries, news aggregator paraphrases. No named analysts, no direct quotes from the calls. Perplexity ended its response by suggesting I try Seeking Alpha Premium for transcript access.

On META, the same query returned named analyst Q&A from Morgan Stanley, Goldman Sachs and JPMorgan, with specific Zuckerberg quotes and 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.

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 larger companies it has; for smaller names (and that includes plenty of US ones, not just the UK minnows) you fall back to a plain web-search summary. That fallback is 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, the citation is verifiable. That distinction matters: ask a general-purpose AI for a revenue number and it will 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.

What the free tier actually includes: 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 the 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, a nice touch for a free tier, if it has survived the rebrand.

The 10-prompt monthly limit sounds generous until you use it in anger. I watched mine drain inside a single sitting: a real fundamentals session (revenue, margins, the cash a company actually generates, what it spends on big assets, how each part of the business is doing) burns three or four prompts before you’ve answered the first real question. 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 is not enough to see a full cycle in a business that’s seasonal, or that swings with the economy, or that has 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 have 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.

The honest catch, current as of June 2026: the free tier runs on a roughly 32,000-token context window, about fifty pages. 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, so a long document has to be fed in chunks rather than held whole. That’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.

What the free tier actually includes: File upload (up to 10 files a prompt), a roughly 32,000-token context window (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/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” or “Find every place the words ‘one-off’ or ‘non-recurring’ appear and quote the surrounding paragraph” 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, because it states the wrong one with exactly the same composure as the right one.

Where it falls short: If you ask Gemini for a balanced view, you’ll get the company’s version of balance. Make the prompt adversarial or 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: congressional trading, insider transactions, government contract awards, lobbying spend, institutional holdings, ETF flows. This is not 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.

What the free tier actually includes: Congressional trading tracker, insider transaction data, government contract awards, lobbying spend, hedge fund holdings, ETF flows. All sourced from public disclosures. Backtesting and real-time alerts are paid.

It supplies the signal; you do the interpretation. 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. 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 platform gives you the raw disclosure data, not the reading of it.

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 this is 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 a place to verify what the AI just told you, and most of the obvious verification options (Yahoo Finance, broker apps) are either ad-cluttered or thin on international coverage. StockAnalysis covers more than 130,000 stocks globally, including the international names Perplexity Finance ignores.

What the free tier actually includes: Full financial statements, ratios, 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 have 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. This is 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 doesn’t have an opinion to defend. This is the step most people skip. A sourced AI answer feels checked because it has 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 have 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 toward saying plainly when it isn’t sure, rather than the false-confident summarising that Gemini drifts into. If you want the AI to push back, Claude is the one that will.

What the free tier actually includes: Claude Sonnet 4.6 (the free default since early 2026), web search and limited file upload, both counting against a rolling usage cap that refills every five hours rather than once a day (Anthropic switched to that window in April 2026).

This is 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 (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, downside, and what would invalidate the view; VERDICT: one action, with a confidence level) turns into something that argues back properly. 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. Output quality is entirely determined by the inputs. 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 have 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), this is the difference between a working tool and one that pretends Europe doesn’t exist.

What the free tier actually includes: 2 years of historical financials, stock and ETF data, fundamental metrics, charting, 2 watchlists, 2 custom screens, limited macro dashboards.

The honest limit is data depth. Two years of history is a snapshot, not a pattern. You need at least five years to see where sales are heading, whether margins are widening or narrowing, or how the business behaves across a full economic cycle. 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: Two years of history is enough for a snapshot but not a pattern. At free, Koyfin shows you what the platform can do, not what you can do with it. Worth noting: 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

These seven cover the early-to-middle stages of a research session: first pass, fundamentals, document analysis, alternative data, verification, sceptical reasoning, data terminal. They don’t cover everything. 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. Real-time alerts are paid everywhere.

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.

What didn’t make the list

ChatGPT free. The exact message allowance keeps moving, 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 appears 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 someone else holds the off switch.

Most of the tools that didn’t make this list have a paid tier that promises to beat the market. None of them publishes audited returns. The tools 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.

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.