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.

I really like P123 works I really like P123 works. The criteria for screens are easy to create and change. It's not a dumbed down version like I've seen on other sites. The backtesting is an interesting and useful feature. To get a 5 star rating you would need to (1) change FCF to exclude dividends (that is so weird and causes me more work to get around), (2) add Invested Capital as a criteria in screening (this would also save me a lot of work), and add foreign stocks to screening universe (I wish you luck in this endeavor. At this point I cannot contribute.)

If you want to have quality data for… If you want to have quality data for everything from fundamental analysis to advanced machine learning there is no better place. Personally, I have used it for advanced machine learning. The downloads and tools are perfect for this. It can give you excess returns with everything from simple regressions to XGBoost and neural-nets. I think if you like machine learning there is no other place to be. It has worked and continues to work for me. I have been a member for over 10 years. Also keeping track of your investing is easier and better than any other site I have looked at. Automatically editing your buy and sell prices, Giving equity curves, Sharpe ratios, alpha etc Put more simply it will make you money. This is true for a lot of different investment styles (mine being machine learning). And you can keep track of what is working best for you over time. If I could give it a higher rating, I would (which serves to illustrate I was never all that good at fractions in school). But P123 is a useful tool even for me. I recommend that you try it. I do not think you will regret it—assuming you like quality data to use for your own investing methods.

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.

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.