The new Carbon Calculator is coming
The Carbon Calculator is moving into the Supply Chain Sustainability School, bringing company carbon reporting, Scope 3 supplier reporting and carbon learning into one connected platform.
A limited beta version is currently available to Scope 3 Carbon Calculator partners. Suppliers and other users should continue using the current Carbon Calculator until the full version launches on 29 August 2026.
Existing accounts and historic data will be migrated to the new platform, so existing users will not need to start again.
What is the Carbon Calculator?
The Carbon Calculator helps organisations to measure, report and manage carbon emissions.
It includes:
- My company emissions: enabling organisations to calculate and manage their own carbon footprint
- My supply chain emissions: enabling Scope 3 Carbon Calculator partners to collect emissions data from suppliers and sub-contractors, and understand supply chain carbon impacts
Coupled with the School’s carbon learning resources, the Carbon Calculator is helping suppliers and sub-contractors understand carbon reporting requirements and improve the quality of their submissions
The new platform will be accessed through the School company dashboard, making it easier to connect carbon reporting with supplier learning and engagement.
A Complete Approach to Scope 3 Reporting
Scope 3 supply chain reporting is challenging because supplier-reported data is often incomplete, inconsistent or unavailable.
The new Carbon Calculator uses a hybrid approach to help address this.
For Scope 3 Carbon Calculator partners, the platform can combine:
- Supplier-reported emissions data, where suppliers have completed their carbon footprint
- Spend-based estimates, using environmentally extended input-output (EEIO) factors, where supplier-reported data is not yet available
This means partners can build a more complete Scope 3 Category 1 view while continuing to improve supplier participation and data quality over time.
The aim is not to rely on estimates permanently, but to use them as a baseline and gap-filling method while suppliers and sub-contractors are supported to move along the carbon reporting journey towards better, more specific data.
What is Changing?
The Carbon Calculator is moving from a standalone platform to the Supply Chain Sustainability School.
The new platform will include:
- One access route through your School company dashboard
- Company carbon reporting
- Scope 3 Category data collection for partner organisations
- Hybrid Scope 3 Category 1 calculations using supplier-reported data and spend-based estimates
- Improved data quality checks, including checks on turnover values and unusual entries
- More flexible reporting periods to support different financial years
- Simpler sharing, so suppliers can report once and share their data with multiple clients
- Clearer dashboards and reporting outputs
- Guidance, helpdesk support and carbon learning resources
- Migration of existing Carbon Calculator accounts and historic data
Existing Carbon Calculator users will not need to start again. Existing accounts and historic data will be migrated, and users will access the new platform through their School company dashboard after migration.
The Carbon Calculator is Moving! Key Dates
Now until 29 August: The current Carbon Calculator remains available at carbon.sustainabilitytool.com. Scope 3 Carbon Calculator partners have early access to the new Carbon Calculator through the Supply Chain Sustainability School.
29 August: Full data migration and roll-out to the supply chain. From this date, access to the current Carbon Calculator will close. Users visiting carbon.sustainabilitytool.com will be automatically redirected to the Carbon Calculator page on the Supply Chain Sustainability School website. All existing Carbon Calculator data will be migrated to the new platform.
How to Prepare
To prepare for the new Carbon Calculator:
- Go to your Supply Chain Sustainability School company dashboard.
- Check that your company profile includes your Company Registration Number.
- Accept the Carbon Calculator data sharing terms when prompted.
If you are not already logged in, you will be asked to log in first.
Once the new Carbon Calculator is available to your organisation, you will be able to access it through your School company dashboard
Frequently Asked Questions
It includes:
- My company emissions: a free tool for calculating and managing an organisation’s corporate carbon footprint.
- My supply chain emissions: a solution for Scope 3 Carbon Calculator partners to estimate supply chain emissions, collect supplier data and improve data quality over time.
The new platform will also connect users with relevant carbon learning resources, guidance and support through the Supply Chain Sustainability School.
All School users will be able to:
- access the Carbon Calculator through their School company dashboard
- complete annual carbon reports and share it with multiple clients
- use flexible reporting periods that better align with their financial year
- benefit from clearer guidance and improved validation checks
- continue using familiar reporting sections, such as materials, waste and electricity
- access carbon learning resources through the School
The new approach reduces the need for suppliers to manually calculate apportionment percentages. Instead, Scope 3 Carbon Calculator partners will use their own spend data, and the platform will calculate apportioned emissions using supplier emissions intensity and spend-based information.
This should make reporting easier for suppliers and improve consistency for clients.
After full migration, users will access the Carbon Calculator through their Supply Chain Sustainability School company dashboard.
From 29 August, users visiting the current Carbon Calculator website will be automatically redirected to the Carbon Calculator page on the School website.
Other users can still get ready by making sure their School company account has:
- a valid Company Registration Number (CRN)
- accepted the Carbon Calculator data sharing terms
Your Company Registration Number helps us identify your organisation accurately, avoid duplicate company records and link your Carbon Calculator data to the correct School account.
You can view the Carbon Calculator terms and conditions here:
(Carbon Calculator terms and conditions https://www.supplychainschool.co.uk/carbon-calculator-terms-and-conditions/)
Demos & Q&A Sessions
Coming soon!
Interested in Scope 3 Reporting?
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