Best AI Tools to Stress-Test a Portfolio (2026)

Federico Kunze Küllmer is the founder of Moneda, one of the tools compared here.

Short answer: A stress test asks one question: what would happen to my money if a bad year came back? Some tools replay real crashes against your holdings. Others run thousands of random futures (a Monte Carlo simulation). General chat assistants can do the maths if you hand them the data. Pick by how much of the work you want done for you, and whether you want to invest in the same place.

• Best overall for individual investors: Moneda (free, Premium from €9.99/month). It replays 2008, 2020 and 2022 on your own portfolio, shows the source behind each figure, lets you import portfolios from other brokers as paper portfolios for the agent to analyse, and you can invest in the same app.
• Best for backtests and Monte Carlo by hand: Portfolio Visualizer (free, Basic $30/month billed annually)
• Best for testing rule-based strategies: Composer (free, Advanced $10/month)
• Best for tracking many brokers in one place: getquin (free, Premium €89.99/year) Best general assistant for your own spreadsheet: Claude (free, Pro $20/month) Best low-cost general assistant: Gemini (free, Google AI Plus €4.99/month)

"Stress test" means something different in almost every tool here, which makes comparing them harder than it looks. This guide puts six tools side by side on the same fields, with prices read from each vendor's own page in October 2026. We compared them from public information. We did not test them hands-on.

Comparison table

Prices as of October 2026, from each vendor's official pricing page.

What to look for

• Real scenarios, not only random ones. A Monte Carlo simulation runs many random futures. Replaying a real crash, such as 2008, shows what an actual bad year did. You want both, because they answer different questions.

  Method	What it shows	Good for
  Historical replay (2008, 2020, 2022)	What a real bad year did to a mix like yours	Seeing an actual worst case and recovery time
  Monte Carlo simulation	A range of outcomes across many random futures	Judging the odds of different results

• Your holdings, not a model portfolio. A test on someone else's mix tells you little about yours.

• Sources you can check. If a tool says your portfolio would have fallen 30%, you should be able to see where that number came from.

• A useful benchmark. Compare against something simple, like an index fund or gold, so the result has context.

• Data coverage. Check which assets it covers: shares, ETFs (exchange-traded funds, baskets of assets that trade like a single share), crypto, bonds.

• Price that fits how often you'll use it. A yearly check doesn't need a pro subscription.

The tools

Moneda

What it is. An investing app for mobile and web, built in Berlin. You research and invest in the same place.

What the AI does. Moneda AI runs on Numa 1, Moneda's financial AI engine. It builds an illustrative portfolio from a goal you describe, or you can import portfolios you hold at other brokers or apps as paper portfolios and have the agent analyse the stocks and your positions. It tracks the portfolio, and tells you when something changes, with a daily briefing on your portfolio and the market. It stress-tests the portfolio against 2008, 2020 and 2022, and benchmarks it against gold, an index or any fund. For single companies, it works figures out from filings such as the 10-K (the annual report US companies file) and live market data, and shows the source behind each one. It gives the bull and bear case, scores a company's 7 Powers, checks quality of earnings, and gives a Moneda Ratio, a descriptive 1 to 7 scorecard. It never tells you to buy or sell. Every trade is approved by you with your passkey, by face or fingerprint.

Moneda MCP lets Claude and ChatGPT reach your Moneda account with permissions you set. You choose what each agent can see and do, and payments are still approved in the app. A REST API and CLI come with Premium and Ultra.

Data covered. Stocks, ETFs, crypto, and a few commodities (gold, silver, oil) through ETFs. You can invest in US-listed shares and ETFs, including fractions, and crypto.

Price. Standard is free. Premium from €9.99/month. Ultra from €19.99/month, with more AI usage and 1, 5 or 10 commission-free trades a month depending on plan.

Best for. People who want to replay real crises on their own portfolio, see the source behind each figure, and act in the same app.

The accuracy numbers Moneda publishes (for example 97.9% groundedness in October 2026) come from Moneda's own tests.

One honest limitation. You can invest only in US-listed shares and ETFs, so no European-listed stocks or funds.

Portfolio Visualizer

What it is. A web toolkit for portfolio analysis. You type in tickers and weights and choose a tool.

What the AI does. The pricing page does not mention AI. The tools are calculators: backtesting (running a portfolio over past prices), Monte Carlo simulation, efficient frontier and portfolio optimisation, factor regression and tactical allocation models.

Data covered. The site says it covers about 187,650 securities across 30 global markets and more than 100 countries.

Price. Free plan. Basic $30/month and Pro $55/month, both billed annually.

Best for. Hands-on investors who want backtests and Monte Carlo runs and are happy to set the inputs themselves.

One honest limitation. No named crisis scenario tool is listed. To see how 2008 hit your mix, you set the backtest dates yourself and read the result yourself.

Composer

What it is. A platform where you build trading strategies without code, backtest them and run them.

What the AI does. Its "Trade with AI" feature helps you discover and evaluate strategy ideas. Paid plans include more AI usage.

Data covered. Not documented on the pricing page.

Price. Starter $0. Advanced $10/month. Pro $32/month billed yearly ($384/year). Business plan by call, price not published.

Best for. People who think in rules ("rebalance when X happens") and want to test a strategy over past markets.

One honest limitation. It tests strategies you build, not a buy-and-hold portfolio you already own, and the pricing page doesn't say which markets it covers.

getquin

What it is. A portfolio tracker that pulls your bank and broker accounts into one net worth view.

What the AI does. Premium adds AI-powered portfolio analysis. The Wealth plan adds unlimited access to AI financial agents, plus financial planning and a retirement plan.

Data covered. Unlimited bank and broker connections and real-time financial data, according to the pricing page.

Price. Free. Premium €89.99/year. Wealth €149.99/year. Excludes country-specific taxes and fees.

Best for. People with accounts in many places who want one view and AI commentary on it.

One honest limitation. The pricing page doesn't list stress tests or crisis scenarios, so check before you pay if that's what you're after.

Claude

What it is. A general AI assistant from Anthropic.

What the AI does. It can work with your files, search the web for current information, and build charts. Connectors link it to other apps, including MCP apps. With Moneda MCP, for instance, it can read your Moneda portfolio within the permissions you set.

Data covered. Whatever you give it or let it reach: your files, the web and connected apps. It has no built-in market data feed of its own documented on the product page.

Price. Free. Pro $20/month, or $17/month billed annually ($200 up front). Max from $100/month.

Best for. People with a spreadsheet of holdings who want to ask open questions, like "what if tech fell 40%?"

One honest limitation. It's general purpose. You supply the data and the scenario, and you should check the maths, because nothing is pre-built for stress tests.

Gemini

What it is. Google's general AI assistant.

What the AI does. Finance-specific stress-test features are not documented on the plans page. Like any general assistant, it can work through a scenario you describe.

Data covered. Not documented on the plans page.

Price. On the German plans page: free, Google AI Plus €4.99/month, Google AI Pro €21.99/month, Google AI Ultra from €99.99/month.

Best for. Trying AI scenario questions at a low monthly cost.

One honest limitation. Same as any general assistant: no built-in stress-test tool, and you supply and check the inputs. We could only read euro prices, so US prices may differ.

How to run a simple stress test yourself

1. List your holdings and the share of your money in each.
2. Pick two or three real bad periods. 2008 (the financial crisis), early 2020 (the Covid crash) and 2022 (rising interest rates hitting both shares and bonds) are a good start, because each hurt different assets.
3. See how far the portfolio fell at the worst point (its maximum drawdown) and how long it took to recover.
4. Compare with a simple benchmark, such as a broad index fund.
5. Ask yourself honestly whether you could have held on through it. If not, the mix may be too risky for you.

FAQ

What is a portfolio stress test?

It checks how your investments would cope with a bad market. Most tools either replay a real crisis or simulate many possible futures.

Is a Monte Carlo simulation the same as a stress test?

Not quite. A Monte Carlo simulation runs thousands of random paths to show a range of outcomes. A historical stress test replays what actually happened in one bad period. Use both if you can.

Can ChatGPT, Claude or Gemini stress-test my portfolio?

They can do the calculations if you give them your holdings and the price data, or connect them to an account through something like Moneda MCP. They have no ready-made stress test, so check their numbers.

Which crises should I test against?

2008, 2020 and 2022 are common choices. They were different kinds of shock: a banking crisis, a sudden pandemic crash, and a year when rising rates pulled down shares and bonds together.

Does a good stress test result mean my portfolio is safe?

No. It shows how your mix would have behaved in past crises. The next one may look different.

This guide is for information only and is not investment advice.