The advancement of information technology has made hyper channels for sales initiatives possible. One emerging channel is instant messaging. Instant messaging (such as mobile chatting) is a prevalent sales channel for today online shop. There are two fundamental reasons for the adoption: 1) easy to install 2) high customer personalization. Unfortunately, the asynchronous natures of the channel have led to the difficulties of measuring salesperson performance. Distinct to synchronous communication in which two involved parties should concurrently active during the communication process (such as telephoning), the asynchronous communication does not require so. As a result, long response does not necessarily mean that the communication process fails and the sales closing invalidated. While there are plenty available methods to measure sales performance over non instant messaging platforms, the method to gauge sales performance over instant messaging platform still under searched. Hence, this research develops a method to assess salespersons performance. For the methodology, there are three steps namely analyzing mobile chat transcript, identifying relevant variables, and defining suitable measurement. The identified variables and their measurements will be the new indicators. To this point, we use real data set from a Japanese-style cookware online shop called forbento.com. The result of this research are five performance indicators, namely response time, sales closure rate, sales product quantity, sales amount, and product variant
