The KDJ indicator is also called the stochastic indicator. It is a technical indicator used in the futures market and created by George Lane. The KDJ indicator first appeared in the form of the KD indicator, and the KD indicator was developed on the basis of the William indicator. However, the KD indicator only determines the overbought and oversold conditions of a stock. The KDJ indicator incorporates the concept of moving average speed to form a more accurate basis for buying and selling signals. In practice, the K line and D line are used together with the J line to form the KDJ indicator.

Among the three curves of the KDJ indicator, the J line fluctuates most frequently, followed by the K line, and the D line fluctuates least frequently.