May 20 is World Metrology Day, which is celebrated to commemorate the anniversary of the signing of the Convention on the Meter in Paris in 1875. This agreement provides the basis for a globally coherent measurement system that is the foundation of scientific discovery and innovation, industrial production and international trade, as well as improving the quality of life and protecting the global environment.

The theme of World Metrology Day 2026 is "Metrology: Building Trust in Policy Making", which highlights the role metrology plays in providing scientific evidence and legal frameworks that policymakers can use to make informed, transparent and enforceable decisions. Metrology, ultimately, represents the foundation of evidence on which public policies are based, frameworks that protect society, as well as support for economic and social stability. When reliable measurements are applied consistently, trust is not only retained in the data – it is also transferred to the institutions, agreements and decisions based on it.

Every day, scientific and legal metrology work continuously to ensure that the global metrology system supports consumer protection and fair trade, enabling markets to function smoothly. From ensuring accurate energy and fuel measurements, to facilitating market transactions, transport safety and environmental monitoring, this agreed framework enables measurements to serve as a reliable basis for decisions that affect citizens, markets and cooperation between countries.

All over the world, national metrology laboratories are intensively advancing the science of measurement by developing and validating new measurement techniques at the necessary level of sophistication. National Metrology Institutes participate in measurement comparisons coordinated by the International Bureau of Weights and Measures (BIPM) or regional metrology organizations, to ensure the reliability of measurement results worldwide.

The International Organization for Legal Metrology (OIML) develops international recommendations, which aim to harmonize requirements worldwide in many areas. OIML also operates the OIML Certification System (OIML-CS) which facilitates the international acceptance and global trade of regulated measuring instruments.

These international metrology systems provide the necessary assurance and confidence that measurements are accurate, providing a solid foundation for global trade today and helping us prepare for the challenges of tomorrow.

World Metrology Day recognizes and honors the contributions of individuals working in intergovernmental, regional and national metrology organizations and institutes throughout the year. In November 2023, a significant step was taken when the UNESCO General Conference, during its 42nd session, officially recognized May 20 as World Metrology Day. In this way, the key role of metrology in the improvement of global scientific cooperation is highlighted, and at the same time, new opportunities are opened for the promotion of metrology, aligning with the mission of UNESCO to build a better world through science and education.

On this World Metrology Day, we invite the global metrology community to reflect on the role that reliable measurements play in decision-making, and to recognize the cooperation and shared commitment that make this trust possible.

We look forward to celebrating May 20th with all of you!

More at: https://www.worldmetrologyday.org/