Uneven distribution of temperature in the chamber water bath can cause the temperature conditions in the chamber are not the same. Temperature, humidity, atmospheric pressure, and dust particles are the main factors which adversely affect the accuracy of water bath’s temperature. Therefore, the purpose of this study is to design a calibration device for water bath with number of channel 6. In this study the system can detect temperatures at each chamber point. The K-type Thermocouple sensor is used to detect the temperature at each chamber point with the help of the MAX6675 module as a signal conditioning amplifier. The sensor readings will be displayed on a Personal Computer using a USB cable, the sensor readings can be stored on a Personal Computer in the form of a TXT so that data can be reprocessed using Microsoft Excel for further calibration purposes. This study aims to facilitate the calibration process and the processing of calibration data. The results of digital measurements obtained a temperature error value of 40 ° C channel 1 1,4 %, channel 2 1.8%, channel 3 0.4%, channel 4 0.2%, channel 5 0.2% and channel 6 0.2%.Temperature 50 ° C channel 1 2.25%, channel 22.26%, channel 3 2.00%, channel 4 2.44%, channel 5 2% and channel 6 1.6%. S.uhu 60 ° C channel 1 0.3%, channel 20.6%, channel 3 0.5%, channel 4 1.5%, channel 5 2% and channel 6 1.8%. Based on the test results, this module has the lowest error of 0.2% and the highest error of 2.44%. The results of this research can be implemented as a Water Bath calibration tool to maintain the temperature stability of the instrument