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Time and frequency services

We have the most accurate time and frequency services in Australia. We measure time and frequency, calibrate instruments and deliver research, advice and training.

We provide services to clients from a broad range of sectors. Our clients are from laboratories, universities, industry and government.

This includes clients from other laboratories accredited by the National Association of Testing Authorities (NATA). Our services include:

  • precision instrument calibration and testing
  • time and frequency dissemination
  • WebTimer, our low cost service for verifying stopwatches and timers
  • consultancy, including advice on quality assurance
  • contract research and development
  • customised training in time and frequency measurement.

We deliver our client services in our Lindfield facility. This is the same laboratory where we conduct research and development to develop and maintain the national standards for time and frequency. 

Time and frequency calibration and testing services

We calibrate most reference grade instruments, equipment, systems and standards that measure time and frequency. We calibrate to the national standards which we maintain. Measurements made with instruments we calibrate are traceable to the national and international standards for time.

Instruments and standards we calibrate

  • oscillators
  • counters
  • synthesizers
  • phase meters
  • tachometers
  • stroboscopes 
  • stop watches
  • custom-built devices.

For enquiries about calibration email

Time and frequency calibration and testing capabilities

Our uncertainty capabilities are the lowest possible in Australia, which means our calibrations are the most accurate. Our uncertainties are as low as 20 ns for time, and 2·10-13 for frequency.

Our time and frequency measurement capabilities are NATA-accredited. NATA publishes our capabilities as part of the accreditation process. This includes measurement ranges for instruments we calibrate and test, with associated uncertainties of measurement. For more information, see our NATA Scope of Accreditation: NMI Time and Frequency Project

Turnaround times

Times vary depending on demand and complexity. We liaise with clients to meet their schedule requirements wherever possible. Typical timing is:

  • wait time: 2 to 4 weeks
  • turnaround time: 2 to 3 days
  • calibration report: 1 to 2 weeks.

Indicative service costs

Our services are for clients who need the highest accuracy possible. This includes other NATA-accredited laboratories. Most NATA accredited laboratories provide results traceable to the national standards. These laboratories can provide a lower-level calibration service that suits the needs of many clients, at more competitive rates. 

Service costs

We don’t provide a set price list for our calibration services. We customise our service and quotation to meet each client’s needs, for each instrument.

Time and frequency dissemination service 

We provide Australia’s official time and frequency dissemination service. This is for users who need to know accurate time of day, traceable to Coordinated Universal Time (UTC) Australia (AUS).

Our time and frequency dissemination services are:

  • a global positioning system (GPS) time-transfer system
  • GPS monitoring and time-transfer data
  • network time protocol (NTP) servers
  • dialup synchronisation through the Automated Computer Time Service (ACTS). 

GPS time-transfer systems

We offer services based on our GPS time-transfer system. This is for clients who need traceable time of day or continuous frequency calibration.

We have 30 NMI GPS time-transfer systems operating throughout Australia and the Asia-Pacific region. Each system combines a GPS timing receiver and computer, with custom data-logging and processing software. The key features of our system are:

  • remote operation via the Internet
  • ability to operate as an NTP server
  • adaptable and customisable to suit client needs. 

For more information or a customised quotation, email or phone +61 2 8467 3501.

GPS monitoring and time-transfer data

Time-transfer data from GPS receivers at our Lindfield laboratory are available in rinex and cggtts file formats at These can be used to establish traceability to UTC(AUS) from a user’s GPS receiver.

We also report daily values for the frequency offset between our GPS receivers and UTC(AUS) at

NTP Servers

We operate Network Time Protocol (NTP) servers across Australia. Our NTP servers are traceable to UTC(AUS). We publish traceability data on our time data repository at

Users must register their computer for our NTP service, and have a static IP address. Our NTP servers won’t respond to computers with unregistered IP addresses. To register, email

Telephone dialup service for synchronising computers

We offer a telephone dial-up service for synchronising computers. This is for clients who can't access our NTP servers through the internet.

Our dialup service uses the Automated Computer Time Service (ACTS) protocol. ACTS doesn't work with digital modems, such as cable, wireless and Digital Subscriber Line (DSL) modems. 

This service will cease on October 31, 2021, when migration to the NBN is completed at our location.

For further information email

WebTimer service for stopwatch and timer verification

The WebTimer is a web-based service for verifying stopwatches and timers against a traceable standard for time. It is commonly used by laboratories to satisfy NATA guidance for regular timer verification. The annual fee for a subscription is currently $55. Time-interval measurements reported by the WebTimer are  traceable to the Australian primary standard for time, UTC(AUS).

The WebTimer measures the time interval between two clicks of a button on a user’s computer. It also calculates and reports the measurement uncertainties on-screen. Users can print and save a report of their time-interval measurement that documents uncertainties and traceability. There is a  sample report available for download.

For more information, or to access the WebTimer:

The WebTimer can be accessed at For more information, email

Consultancy services

We work with clients to understand their measurement issues or opportunities. We deliver services in:

For more information about our consultancy services email

Training and education

We provide time and frequency measurement training and education for industry. We offer short-courses through our training and assessment program and deliver bespoke training directly through our laboratory. Our courses cover topics such as:

  • measurement principals and techniques
  • traceability and standards
  • calibrating instruments

We can customise training for individuals or teams including training to use instruments, systems and standards we design and manufacture. 

For more information email

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