Time in the city
We provide time services to support industry, enable innovation and deliver confidence.
Why NPL?
In 1955, timekeeping in the UK reached a turning point when Louis Essen, a physicist at the National Physical Laboratory (NPL) developed the world’s first working caesium atomic clock.
And today..
As the home of UK time, we maintain the national time scale and disseminate time across the UK. We contribute to global timekeeping and the global reference time system, Coordinated Universal Time (UTC). By applying very fine adjustments to atomic clock frequencies, UTC(NPL) is kept within a few nanoseconds of UTC.
Our expertise in maintaining time standards helps keep our daily lives running on time with accurate timekeeping that is crucial to our quality of life. The accuracy of timekeeping impacts on everything satellite navigation systems, underpins the functioning of the internet and facilitates timestamping for transactions in financial trading.
Our ability to measure time to this accuracy helps drive economic growth for the UK with trusted timestamping for the finance sector down to the millisecond. We operate two commercial time services, NPLTime Certified® and NPLTime Access®
Upcoming webinar
Resilient time: Delivering impact for the UK – you will be able to find out more about why NPL is the home of time in the UK and how our NPLTime Certified® and NPLTime Access® services are supporting industry through providing a secure resilient timing signal independent of GNSS.
Join us on 10 September 2024 at 16:00 (UTC) to find out how your sector could be benefitting from the tight synchronisation of systems and traceability to a common reference time scale.
Register for webinar
Hear from Nicolas Bonnet, Director at ICE
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Time travel on the Thames
In September 2023, to showcase the story of time we presented the Royal Museums Greenwich with a state of the art strontium ion clock, celebrating the relationship between two organisations who have had, and continue to have, a substantial impact on how the world tells the time.
A flotilla of boats, led by the Jubilant, rowed from Isleworth to Royal Museums Greenwich, carrying the gifted atomic clock. This momentous occasion marked 21 years since the Jubilant first carried an NPL atomic (caesium) clock down the River Thames.
The strontium ion clock was the most accurate atomic clock in the world in 2004 and consists of a single ion of strontium trapped and cooled within the vacuum chamber. Our latest optical clocks are more than 100 times more accurate, and one has recently started contributing to International Atomic Time.
We continue to showcase the importance of accurate and resilient timekeeping in our daily lives. Through our longstanding relationship with Royal Museums Greenwich, the clock now provides the public the chance to view a prestigious piece of scientific equipment and learn about its vital role in the UK’s timekeeping history.