I started using portfolio123 around 19… I started using portfolio123 around 19 years ago. Simply the best product for quantitative stock analysis. No other come even close. The only solution you need for your stock investment assuming you have the time and desire to learn factor investing.

Extremely powerful and unique tool Extremely powerful and unique tool. Im not aware of any other like it on the market. Despite having no formal finance background I have decisively beaten my benchmark index for multiple years with real money investing in companies that are off most other people's radar. Once you get used to systematically investing with a model you will wonder how you did it any other way (or how you could do it any other way). The staff is extremely knowledgable and responsive. The user community is generous and supportive. Beyond that, the tool is just fun to research, test theories and play around with.

Nearly 10 Years of Superior Service - Small Token of Appreciation Number one priority for any serious investor is 'quality of data', as well as functionality and ease of use. P123 is easy to learn and get going with, and allows you to learn fundamental factors/codes at your own pace. I have been using the service for nearly 10 years now, and it is very much a part of my development (still ongoing) as a disciplined investor/analyst religiously focused on company fundamentals (and a sprinkle of technical timing). No screener, or backtesting software is worth it's salt without the highest quality and integrity of data. And P123 scores 5/5 on that highest priority. It's been good to me - hence this lengthy review as a small token of appreciation.

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.

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.