Best wishes for 2025!

LNE is celebrating a historic anniversary for the world of measurement. The year 2025 will mark the 150th anniversary of the signing of the Metre Convention. To mark the occasion, the year will be punctuated by events during which scientists, researchers and engineers will demonstrate how metrology has helped to shape our world and how it is shaping our future and helping us to meet the major challenges of our time.

2025, the historic anniversary of the signing of the metre convention

Signed in 1875 by 17 States, the Metre Convention established the decimal metric system and a worldwide harmonisation of units of measurement, essential to guarantee the reliability of scientific, industrial and commercial exchanges.

The origins of the metric system can be traced back to the French Revolution, when the Constituent Assembly decided in 1791 to create ‘a unit that is neither arbitrary nor peculiar to the situation of any people on the globe’. This ambition gave rise to the great scientific epic led by the astronomers Delambre and Méchain, who measured a fraction of the earth's meridian between Dunkirk and Barcelona in order to establish the length of the metre, the founding unit of the metric system. Since then, the fundamental units have continued to evolve in line with scientific and technological advances.

Today, the SI is based on seven fundamental units - the metre, the kilogram, the second, the ampere, the kelvin, the candela and the mole - all of which have been redefined since 2018 on the basis of fundamental physical constants, in particular those derived from quantum mechanics. This progress ensures unprecedented precision and universality. LNE and the French metrology laboratories*, as reference laboratories in France, have played a major role in these redefinitions, notably for Planck's constant (kilogram), the electric charge (ampere) and Boltzmann's constant (kelvin).

*French metrology laboratories : LNE, LNE-CNAM, LNE-OP, LNE-LNHB/CEA, LNE-Cetiat, LNE-ENSAM, LNE-IRSN, LNE-LADG, LNE-LTFB , LNE-Trapil

The LNE Group devotes 20% of its budget to scientific research, an essential activity for innovation and industrial and economic development. It develops new measurement standards and methods adapted to emerging technologies, alongside institutional, academic and industrial partners. As the national metrology institute, guarantor of national standards and pilot of the RNMF, LNE helps industry and public authorities to meet the challenges of competitiveness, energy savings, health and safety, the environment, etc.

LNE wishes you all the best for 2025

More information

On metrology in France: website RNMF

On units of measurement: file on understanding the SI