The QUANTUM Data Quality Labelling Tool is a key component of the European Health Data Space (EHDS) initiative, designed to address the challenge of ensuring that health datasets are of high quality, accessible, and interoperable across EU member states. As healthcare data plays an increasingly vital role in research, policy, and innovation, this tool provides a standardized mechanism to evaluate and label the quality, utility, and maturity of datasets, supporting stakeholders such as healthcare institutions, research organizations, and policymakers. The QUANTUM Labelling Tool primarily operates as a standalone application for collecting DQ&U and maturity evaluations. The tool does not connect to external APIs or third-party systems for automated data exchange. Consequently, the use of the Interoperability Test Bed is not directly applicable. Interoperability is ensured by using standard semantic representations (e.g., RDF and DQV) to export evaluation results.