A stock screener is a tool that searches the shares traded on one or more markets and returns those that meet conditions set by the user. Typical filters include market capitalization, sector, valuation measures such as the price-to-earnings ratio, dividend yield, earnings growth, trading volume and readings from technical indicators. Screeners are offered by brokers, financial websites, data vendors and charting platforms such as TradingView, and range from free tools with a few fields to professional systems with thousands.
A screener reduces thousands of securities to a short list for closer study. It is the manual counterpart of the ranking step in factor investing. Its results depend on the quality and timeliness of the underlying data, and a share that passes a filter is not thereby a sound investment: screens describe the past, can favour companies with distorted accounts, and say nothing about matters that numbers do not capture.