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Calibration
Services

A comprehensive range of services

NPL provides UKAS-accredited calibration services across a wide range of measurement disciplines. As the UK’s national metrology institute, we have traceability directly to the SI units and often have lower uncertainties than those offered by other accredited laboratories.

Why use NPL for calibration?

  • Easily accessible, good response times and rapid turnarounds
  • Interpretation of results, if required
  • Bespoke, as well as standard, calibrations  
  • Accredited by UKAS to ISO 17025

Services for new instruments or those at the very leading-edge of metrology capability and are delivered under NPL's ISO 9001 compliant quality system.

Arrange your calibration today

We can help you to…

  • Calibrate laboratory equipment
  • Meet ISO requirements
  • Demonstrate measurement traceability
  • Improve measurement confidence
  • Support accreditation activities

Let us know how we can help and an expert will be in touch.

Contact us

Find a calibration service

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Chemical calibration
Dimensional calibration
Electrical calibration
Force, pressure and mass calibration
Fibre optics and transmission calibration
Gases and particles calibration
Ionising radiation and radioactivity calibration
Optical radiation calibration
Radiation force balances calibration
Temperature and humidity calibration
Time and frequency calibration

UKAS accreditation

Frequently asked questions on calibration

What is calibration?

For measurements to be trusted they must be comparable to those made by other people or at different times. Calibration is a process in which an instrument or piece of equipment's accuracy is compared with a recognised standard. The timely and correct calibration of measurement equipment is essential for compliance with standards and for trusted measurements. As an NMI, NPL provides calibrations with the lowest measurement uncertainties and with traceability to the primary standards.


What are calibration artifacts?

Calibration artefacts are reference items with known, trusted properties that allow manufacturers to verify and correct the performance of their measurement systems. By comparing an instrument’s readings against an artefact of known size or characteristics, users can identify and reduce bias, ensuring their measurements remain aligned to an agreed reference. This independent check helps confirm that instruments are operating accurately and consistently. They help monitor the accuracy of measuring machines, coordinate measuring machines, multisensor devices, CT measuring machines or surface measuring devices.

Calibration of OTDR reference artefacts

Precision scales, stage micrometers and graticules

Step gauges

Surface temperature test phantom

How often should equipment be calibrated?

There are no set rules in place that govern when an instrument should be calibrated. If your organisation carries out measurement using any form of instrument, then you need to be able to prove that the instrument provides accurate and reliable readings. Annual calibration is common practice, or you can follow your own Quality Management Systems. We can help you to determine the recalibration period and then arrange it.


What are reference materials?

Reference materials are stable, well characterised substances with property values known to high confidence. They are used to check, validate and calibrate measurement processes. They provide a trusted benchmark for ensuring accuracy, comparability and traceability. Certified reference materials include documented values, uncertainties and traceability to recognised standards.

Gas reference materials