QuantGPT vs Portfolio123

Updated October 2026 · Written by QuantGPT, the maker of one of the two, so read it knowing that

// THE SHORT VERSION

Portfolio123 is a research platform for rules-based stock investing. You rank stocks on fundamental and technical factors with spreadsheet-like formulas, backtest screens, ranking systems and strategies on point-in-time data, train machine learning models with AI Factor, and send orders to your broker.

QuantGPT is the data and trading platform for AI. Claude, ChatGPT, Cursor or any MCP client runs backtests in seconds over one URL, with no code to write, on decades of US stock history. QuantGPT never manages a trade: you trade at your own broker, or your own code does through QuantGPT Cloud on QuantGPT Pro.

If you build multi-factor ranking systems and want the deepest tools for that, Portfolio123 is built for that. If you want your own AI assistant to run the backtests in plain English, that is what QuantGPT is for.

// WHERE PORTFOLIO123 IS STRONG

First, what Portfolio123 does well, from its own pages, checked 2026-10-28 (every source is listed at the end).

• No codeScreens, ranking systems and strategies are spreadsheet-like formulas built from pre-built factors, such as the Piotroski F-Score, with no programming.
• DataPoint-in-time data with no survivorship or look-ahead biases, in its words, powered by FactSet, with S&P Global's Compustat and CapitalIQ available under a data license.
• CoverageOver 15,000 current US, Canadian and European stocks, with many thousands more in the past, and up to 20 years of backtest history; ETF history from 1999.
• StrategiesRanking, separate buy and sell rules, custom universes, position sizing and hedging in one strategy; books of strategies run together; simulations with slippage and commissions.
• AIAI Factor trains machine learning models, such as XGBoost and neural networks, without code, with blocked k-fold cross validation, and its predictions feed ranking systems and backtests.
• ManageConnect your brokerage account, send orders to your broker from Portfolio123, and follow models built by its team and expert users.
• YearsPortfolio123 has been refining its research tools since 2004.

// SIDE BY SIDE

// WHERE QUANTGPT DIFFERS

Your AI runs the backtest, in the chat you already use

QuantGPT is the data and trading platform for AI. Connect Claude, ChatGPT, Cursor or any MCP client once, at one URL, and your AI searches the library, runs a backtest in seconds and reads the result mid-conversation. The computation runs on our side, and the answer comes back with the numbers that produced it. Guides: connect Claude, connect ChatGPT, connect Cursor.

Decades of US stock history

A QuantGPT backtest can run a rule across the whole US stock market from 1998, with companies that later delisted in the universe, and each result shows every calendar year beside the benchmark. Every backtest is also split at a year (2015 by default) and judged on the years after it. Our daily bars can be checked one at a time against any independent source on the public verify page.

Lessons that play without an account

Three lessons run on real market data with no sign-in: arm your AI, become a quant, run the backtester. Start with learn quantitative investing, a written lesson on one real trend rule.

// WHO SHOULD USE WHICH

Portfolio123, if you

• build multi-factor ranking systems on fundamentals and want point-in-time data to test them;
• invest in Canadian or European stocks as well as US ones;
• want to train machine learning models on fundamentals without code;
• want to send a strategy's orders to your broker from the same site.

QuantGPT, if you

• want your own AI assistant, Claude, ChatGPT or Cursor, to run backtests mid-conversation;
• want to test an idea on US stocks across decades and market regimes, without code;
• want a rule run across the whole market, companies that later delisted included from 1998;
• place your own trades at your own broker, by hand or, on QuantGPT Pro, with your own code on QuantGPT Cloud.

Both, if you

want to ask your AI a quick question across decades of US stock history, then build the idea into a full ranking system on Portfolio123.

// HOW THE FIELD SPLITS

If you chart and write Pine Script, read QuantGPT vs TradingView. If you want no-code technical strategies and bots, read QuantGPT vs TrendSpider. If you write Python or C#, read QuantGPT vs QuantConnect. Seven platforms side by side: backtesting platforms compared, 2026.

// QUESTIONS

What is the best Portfolio123 alternative for AI?

It depends on what you want the AI to do. Portfolio123's AI Factor trains machine learning models, such as XGBoost and neural networks, on its point-in-time data and uses their predictions in ranking systems and backtests, with no code. If you want an AI assistant such as Claude or ChatGPT to run the backtests for you in plain English, QuantGPT is built for that: one MCP URL, and your AI searches the strategy library, runs backtests in seconds and queries decades of US stock data.

Do I need to code to use Portfolio123 or QuantGPT?

No, for either one. Portfolio123 screens, ranking systems and strategies are spreadsheet-like formulas built from pre-built factors. On QuantGPT you pick a documented strategy and set its parameters, build criteria in the terminal, or ask Claude or ChatGPT in plain English once it is connected.

Which one has more history?

It depends on the plan and the market. Portfolio123 backtests 5 years of point-in-time stock data on Screener, 10 on Backtest, 15 on Portfolio and 20 on Ultimate, in the US and Canada or Europe and the UK, with ETF history from 1999. QuantGPT backtests US stocks from 1998 by default, with companies that later delisted in the data from 1998 on and survivors only in earlier years; fundamentals are joined by filing date, and the S&P 500 index goes back to 1928.

Can QuantGPT send orders to my broker like Portfolio123?

Yes, with your own code. QuantGPT never manages a trade: QuantGPT Cloud, on QuantGPT Pro, hosts code you write or adopt and sends its orders to your own brokerage account under your own keys (Alpaca today, paper and live accounts), using only the broker's own order types. Portfolio123's Manage connects your brokerage account so you can send orders to your broker from Portfolio123.

What does each one cost?

Portfolio123, as of 2026-10-28, for the US and Canada: Screener at $35 a month or $300 a year, Backtest at $116 or $1,000, Portfolio at $174 or $1,500 and Ultimate at $278 or $2,400, with 30 days of Screener and Backtest access at no cost. QuantGPT is $49 a month and QuantGPT Pro $149 a month, each starting with a 3-day free trial with a card up front; Business starts at $1,499 a month.

// PUBLISHER DISCLOSURE

QuantGPT LLC publishes this page and makes QuantGPT, so we are not a neutral party. We are not affiliated with Portfolio123, it did not review or endorse this page, and the links to its pages have no affiliate code: we earn nothing if you choose Portfolio123. We compared public product pages and documentation; we did not run the same strategy on both platforms. Every fact about Portfolio123 comes from its own public pages checked 2026-10-28, listed below, and plans and features change, so check there before you decide. Every QuantGPT number comes from our own plans and product. If something here is wrong, write to desk@quantgpt.co and we will correct it.

// SOURCES: PORTFOLIO123'S OWN PAGES, CHECKED 2026-10-28

1. portfolio123.com20 years of backtesting data across the US, Canada and Europe; 30 days of Screener and Backtesting access; send orders to your broker.
2. portfolio123.com/researchNo programming; spreadsheet-like formulas from pre-built factors; point-in-time data, FactSet, Compustat and CapitalIQ under a data license; strategies, books, slippage and commissions; over 15,000 current stocks; since 2004.
3. portfolio123.com/ai-factorAI Factor: no code, XGBoost and neural networks, blocked k-fold cross validation, predictions in backtests.
4. portfolio123.com/sv/register/retailNon-professional plans and prices, monthly and annual; a second region at 40% more; history by plan; ETF history from 1999; AI Factor at an added cost; live and simulated strategies; no credit card for the 30 days.
5. portfolio123.com/investManage: broker connectivity, orders sent from Portfolio123, models to follow.
6. portfolio123.com/research/dataminer-apiThe API: simulations, uploads and data for machine learning; DataMiner with no code.

QuantGPT's numbers come from its own plans and product: the plans on the pricing page, the strategy library, and the data limits on the disclosures page.

// MORE COMPARISONS

Backtesting platforms compared, 2026 · QuantGPT vs QuantConnect · QuantGPT vs Composer · QuantGPT vs TradingView · QuantGPT vs TrendSpider · QuantGPT vs the EODHD MCP server

Try QuantGPT: start your 3-day free trial, cancel any time, or play lesson 1 without an account.

Facts about Portfolio123 are from its public pages, checked 2026-10-28, and may have changed. The names of other companies and products belong to their owners; no affiliation or endorsement is implied. QuantGPT is a research tool, not investment advice: backtests are hypothetical, and past results, real or simulated, do not predict future results. The terms govern.