Nowadays data-driven applications are gaining ground. Analyzing data and improving data quality is important for the proper functioning of these applications. In the thesis I present the concept of data quality, its typical statistical metrics and its statistical and visual presentation methods. I also detail the design, construction and implementation of an application developed in my chosen programming language as well as how the language supports the evaulation of the data quality. For the implementation I chose the Python programming language. The application was made in the Plotly Dash framework.The application helps to evaluate data quality. With this application, you can get information about the data quality of your uploaded data set. I display information on a dashboard using graphs and spreadsheets. I illustrate how the application can be used, and how the quality of the data has improved as a result, on an example. I also mention the further development opportunity and the area-specific extension.