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Products and services

Time and frequency

A reliable source of timing and synchronisation standards and services

As the UK's home of precise time and frequency measurement, NPL offers a range of services providing access to a reliable and trusted source of time.

Clocks and frequency standards are key to the dissemination of high-accuracy time services to UK science, technology and industry. They ensure compatibility with international time scales through worldwide time transfer and clock comparison. Methods for comparing geographically separated clocks and frequency standards are vital for the development of improved standards, generation of the international time scale and provision of services to UK industry.

At NPL we operate the national time scale UTC(NPL) and the UK primary frequency standards, which contribute to global timekeeping. We disseminate accurate time and frequency to users across the UK, via services such as the MSF radio time signal, our internet time service and NPLTime®, and offer a characterisation service for clocks and frequency standards. 

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Frequency standards, clocks and clock components

We have the capability to supply caesium fountain primary frequency standards to realise the SI definition of time, the components of compact optical clocks and a range of products to deliver global time and frequency signals.

Timing services

The MSF signal offers a reliable source of UK civil time and the internet time service synchronises computer clocks. NPLTime® has microsecond accuracy for finance and other sectors.

Clock and frequency standard calibrations

We calibrate or characterise clocks, frequency standards and GPS-disciplined oscillators against UTC (NPL). Customers can establish whether their frequency standards or clocks, developed either in house or purchased, are operating to specification.

We’re here to help

Still struggling to work out what you need? We pride ourselves on giving sound technical advice to guide you. By combining expert advice, standard tests and bespoke consultancy, you can be confident in our approach.

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Find out more about our expertise in this area, and how we are creating impact from science and engineering.

Case study

Characterising vapour cells for ultra-accurate atomic clocks


Establishing high-accuracy time measurement for optical atomic clocks


Work with us

Our research and measurement solutions support innovation and product development. We work with companies to deliver business advantage and commercial success.
Contact our Customer Services team on +44 20 8943 7070