1 Clinical Trial Carbon Calculator
1.1 What the calculator can do
The calculator is intended to facilitate pre-trial assessments of the carbon implications of trial design decisions, to assist with progress assessments during a trial’s life-cycle and to facilitate post-trial footprinting to aid reporting. It is intended to provide a rapid and simple means to produce indicative numbers on carbon emissions associated with trial activities.
A more detailed or robust assessment may be needed to meet your assessment objectives...
1.1.1 Entering data
Data must first be entered into the General Information and Countries fields. Once these have been completed, the rest of the data entry modules are made live...
1.1.2 Import and export function
The calculator has been designed to temporarily store your data in your own browser cache. This means that if you close and reopen the calculator, the calculator will still have the previously entered data available to edit and review, as long as you are using the same device and browser software.
Once a calculation session has been started and at least the General Information and Countries fields have been completed, the calculator has option to download your entered data. The download will be in the form of a JSON file that is machine-readable. Once you download a JSON file to your own local system, you can then return to the calculator and edit the data to test different trial profiles and design parameters.
If you rename your trial and save a separate JSON file to your local system, you can then begin to compare scenarios. Open two copies of the calculator in separate browser windows, and upload one of your trial scenarios to each calculator. You can then make changes and track the impact of those changes between scenarios.
1.2 What the calculator doesn’t do
There are some important limitations to the calculator’s functionality that users should keep in mind.
1.2.1 Assumptions and factors
The calculator relies on background emission factors and assumptions, for example travel profiles, . The iLCCT collaboration project has collected and generated many individual data points to populate the background reference dataset that the calculator calls on to enable calculation of a carbon footprint relevant to the user’s trial input data.
1.2.2 Report output
The calculator has not been configured to enable reports to be downloaded. Please refer to section 1.1.2 for more information on the current output capabilities of the calculator.
If, after using the calculator, you would like some ideas on how to decarbonise your clinical trial, have a look at the Sustainable Clinical Trial Knowledge Hub for case studies and general tips on running a low-carbon clinical trial.
1.2.3 Calculator development
The calculation steps performed by the calculator and the reference database behind it have been checked to ensure the calculator functions as expected and delivers overall results approximately in line with those expected from a full life cycle assessment. Its functionality and the coverage of trial-appropriate data within the reference database are kept under review and further published versions of the tool will address as many of the current limitations as practicable. Further data is being collected and processed. The capability of the tool to give higher resolution, to rely less on generic defaults and to improve the interoperability with trial design and management data systems will be considered in future updates. The latest version of the calculator (version 3.0) and database were released in April 2026.