The objective of the research is to design a real-time clock with an alarm clock feature, utilizing the DS3231 module on the Arduino UNO platform. The purpose of this project is to develop a functioning real-time clock and conduct subsequent testing. During the course of the project, we established the structure and principle of the real-time clock, developed the microcontroller's software (sketch in Arduino IDE). Additionally, we analyzed the technical specifications and circuit diagram to select the appropriate components, devised a functional scheme and algorithm for the device, and created a program to implement the real-time clock. As a result of our efforts, we successfully built a prototype device using the Arduino UNO microcontroller. This device is capable of displaying the current time on a display, adjusting time parameters, and setting an alarm clock.