Since 2011 this is my main modeling platform - no regrets I have been using this platform since 2011. I have used others, even ones that cost 6-digits per year to license and I can honestly say I prefer this one. I have used ClariFI and WorldQuant to name just 2 of the high institutional grade platforms and about 6 others. The P123 simulation engines are lighting fast, they listen to users and are always adding new features...in fact...after 9 years of using the platform I still probably use only 20% of what it can do. A well-rounded system whether you are running simple screens, custom weighed complex portfolios or in-depth research. Any serious family office or smaller firm should take the time to get one of their guys trained on this platform.

Portfolio123 is an awesome site with so many tools Portfolio123 is an awesome site with so many tools to help investors. They are very responsive and they are often on message boards with help and will respond to emails as well.

Excellent site for backtesting equity trading strategies Excellent site for testing stock and ETF trading strategies. P123 provides a thorough point-in-time database with a powerful and flexible engine to simulate backtests of systems. And they integrate with Interactive Brokers to automate applying those strategies to live trading.

Portfolio123 is a game-changer for… Portfolio123 is a game-changer for stock investors, providing a powerful platform for the design, simulation, and deployment of quantitative financial models. It also has stock screening, charting (including YChart style), trading (via Interactive Brokers and Tradier), macro economics charting, watchlists, an earnings center, cross-section series plotting, external data importer, a data API, stock news, stock summary snapshots, stock comparison tool, sector/Industry performance, fundamental and estimate summaries, a user forum and more (really). In the near future, machine learning will be supported. It's not just another retail-level tool; it's the only one that I’ve found to work in practice. To find something better, I suspect you'd have to go professional and spend significantly more. I've been a loyal subscriber for over a decade, which speaks volumes about its effectiveness. Is there a downside? Sure, building successful trading models is hard work, but with dedication and focus, it's possible to be successful. Whether you're researching stocks, building and simulating quantitative models, or managing accounts, Portfolio123 has what you need.

Very flexible stock screening and backtesting platform This is the best and most flexible platform for stock and ETF screening, ranking and backtesting I know. With main focus on fundamentals, you can test, combine and vary hundreds of parameters. No programming knowledge required. One restriction: Portfolio123 does not support intraday trading.