World Metrology Day is observed annually on May 20 to commemorate the importance of measurement science in our daily lives. In 2025, this global observance continues to highlight how accurate and reliable measurements support innovation, industry, trade, health, and environmental protection.
World Metrology Day marks the anniversary of the signing of the Metre Convention on May 20, 1875, in Paris, France. This international treaty established a framework for global collaboration in the science of measurement, known as metrology. The event is jointly organised by the International Bureau of Weights and Measures (BIPM) and the International Organisation of Legal Metrology (OIML).
Metrology is the science of measurement. It plays a critical role in ensuring accuracy and consistency in everything from manufacturing and healthcare to climate science and trade. Whether it’s the fuel we pump, the medicine we take, or the food we consume—measurement is at the core of quality and safety.
The theme for World Metrology Day 2025 is expected to focus on “Measurements Supporting Innovation”. This theme emphasizes the role of metrology in advancing new technologies, scientific research, and industrial processes, especially in sectors like renewable energy, healthcare, AI, and space exploration.
World Metrology Day serves as a reminder that standardised measurement systems are essential for international cooperation, safety regulations, and scientific progress. It also highlights the continuous efforts by scientists and engineers to improve the precision and reliability of measurements.
Events such as seminars, technical workshops, exhibitions, and awareness campaigns are held worldwide to educate the public and industries on the significance of metrology.