Rainfall is an important parameter in determining weather conditions. Rainfall data can be used for various purposes, such as for consideration in planning a civil building. If rainfall cannot be measured properly, it will result in an inaccurate design. In actual conditions, rain gauges are usually placed in locations far from power sources. However, to obtain data in digital form, a power source is required. In obtaining digital data, electronic components and monitoring systems are needed which require a power source and an internet connection to send measurement data to the website. The rainfall gauge used in this study is of the tipping bucket type. In the rain gauge used, there is a magnetic switch that functions to calculate the tip that occurs when it rains so that the rainfall value is obtained. The rainfall gauge used in this study has an accuracy of 97.85%. This tool is equipped with an IoT-based monitoring system, namely using a website. Based on the results of the tests that have been carried out, and the range of rainfall per 5 minutes that can be measured is 0 mm-74,5 mm, the range of rainfall per 1 hour that can be measured is 0 mm-894 mm, and the range of rainfall per 1 day that can be measured is 0 mm-21456 mm. In receiving data from the rainfall gauge used in this study, the Arduino Mega microcontroller and the GSM 808 module were used to send data reading the rainfall gauge to the website. On the website display, you can see the rainfall that is happening, and you can see a graph of rainfall. There is a report menu that can be used to download rainfall data per 5 minutes, per 1 hour, and per 1 day with the date selection feature of the rainfall data you want to download. Downloaded rainfall data is in the form of an Excel file.