Portfolio123 is a web-based stock investment service that provides everything from model portfolios to stock screening and strategy backtesting. As a financial research platform, they provide a single destination to manage your investment accounts and create, backtest, and manage stock and ETF strategies. Portfolio123 is a pioneer in allowing anyone to create a rules-based investment strategy that closely resembles what a human manager does. Portfolio123 aims to eliminate the time-consuming, repetitie and emotional process of managing a stock strategy.