2025 Carbon Calculator Data Update: What’s changed and what it means for our users
9th September 2025
Great news – we’ve just completed our annual review of carbon factors, benchmarks and assumptions to ensure the carbon calculator stays right up to date. Data updates will be backdated to July 28th, which is when the method 1 endpoints were automatically updated with new BEIS figures. You don’t need to take any action, but you might notice changes in CO2e figures for your most recent Final Footprints and Early Insights, which have been updated automatically for you!
We do it at this time of year because one of the largest sources of AdGreen’s carbon factors (BEIS) publishes their annual data release in late summer, which means everything is fresh for when Adland returns from summer holidays. Other carbon factor sources are updated from time to time too, and these updated numbers are automatically referenced by our tool, thanks to our API with Climatiq.
If you're curious about how it all works, read on for the full methodology.
Why Might My CO2e Change Over Time?
Let’s say a Final Footprint contains multiple entries for the same activity e.g., one hotel night in London. If you add the the activity in June 2025 and add a second entry with the exact same details again in September, you might notice a difference in the CO2e. That’s because the underlying factors may have changed in the interim.
Let’s dig a little deeper…
For each item in an activity area, the tool calculates emissions data using one of three methods:
- Automatic Live Factors from Climatiq
Using specific Climatiq API endpoints, where multiple variables are sent and different sources/factors are used depending on the request detail.
This method is used for energy use, business travel and hotels, and equipment transport. These endpoints are updated with more recent factors automatically.
- Static factors relevant to a defined Climatiq dataset
Using the Climatiq API ‘estimate’ endpoint, where specific factors are used by sending activity label IDs and a source, along with the relevant activity information.
This method is used for almost everything else — things such as catering, wardrobe and art department materials, water use and waste.
The UK government's BEIS department supplies factors for these items and republishes them annually in late summer. AdGreen must update the carbon calculator to point to the newer dataset which contains the latest versions of these factors.
- Static factors not held by Climatiq
Using factors stored in the tool’s back-end database, offline of Climatiq.
This method is used for meals and data storage, and if they change, AdGreen must update the factors manually.
What's the upshot of the 2025 data update?
✅ Latest BEIS figures
These are used for a selection of method 1 calculations (e.g. hotels, cars) and all method 2 calculations. These updates ensure activities which rely on carbon factors from BEIS are as accurate and current as possible.
✅ Method 3 factors confirmed unchanged
We’ve spoken to Albert and Filmlocker, who provide the factors which underpin method 3 calculations for meals, LTO tape and hard drives. Both have confirmed that their data remains up to date and so the factors are therefore unchanged.
✅ Benchmark updates
We’ve reviewed all benchmarks and assumptions used in calculator formulas when users are unlikely to have the information themselves. As a result, two updates have been made:
- Cloud storage market shares have been refreshed with newer figures, slightly adjusting the weighting of carbon factors for the three main providers (AWS, Microsoft and Google)
- The non-shooting spaces electricity benchmark (kWh/day) has been updated based on new CISBE data covering social clubs, day centres, and community centres
✅ Expanded Equipment Trucking Options
You can now select electricity as a power type for all vehicle types no matter where in the world the equipment trucking takes place (except for China, where some restrictions apply).
When Do These Changes Take Effect?
- Data updates have been backdated to July 28th, which is when the method 1 endpoints were automatically updated with new BEIS figures.
- All relevant Early Insights sections, and all Final Footprint activity forms created or edited on or after July 28th will be using the latest factors, regardless of method - those created or edited between July 28th and 9th September (when the data update went live) have been automatically recalculated.
- Items saved prior to July 28th will remain unchanged unless edited. If you update an entry, it will recalculate using the latest available factors.
- The additional options for equipment trucking are effective from 9th September, and are not backdated. Only activities added or edited from this point forward will give the user these expanded options.
Best Practice Tip
To ensure consistency and accuracy, we recommend recording your projects in the calculator as soon as you have the required information. This helps lock in the relevant factors and avoids discrepancies later.
📘 Want to understand more about how the calculator works?
Check out our methodology section, which explains all of the carbon calculator's key principles.
✉️ Questions?
Email us — we're here to help.