The DAX (Deutscher Aktienindex (German stock index)) is a blue chip stock market index consisting of the 30 major German companies trading on the Frankfurt Stock Exchange. Prices are taken from the electronic Xetra trading system. According to Deutsche Börse, the operator of Xetra, DAX measures the performance of the Prime Standard’s 30 largest German companies in terms of order book volume and market capitalization. It is the equivalent of the FT 30 and the Dow Jones Industrial Average, and because of its small selection it does not necessarily represent the vitality of the economy as whole.

Dax or DAX may refer to:

• Data analysis expressions, a language used by the Microsoft PowerPivot software
• DAX (software program), a film and television production workflow application
• Microsoft Dynamics AX, an enterprise resource planning software