What is the route-based calculator?
The route-based calculator is a Scope 3 emissions feature that lets you calculate greenhouse gas emissions based on actual origin-to-destination routes, rather than relying on average activity-based estimates. It is powered by our emission factor partner and is designed for companies with transportation and travel data, such as logistics operations, shipping routes, and business travel itineraries.
Instead of entering a total distance or a generic activity type, you can specify a real journey (e.g. London → Rotterdam by road freight, or London → New York by air) and the platform calculates the associated emissions using route-specific emission factors.
Which Scope 3 categories does it cover?
The route-based calculator is available across the following Scope 3 categories:
Category 4 — Upstream transportation and distribution
Category 6 — Business travel
Category 7 - Commuting
Category 9 — Downstream transportation and distribution
How does it work?
When entering data for a supported Scope 3 category, you will see a route-based method option alongside the standard activity-based and direct entry methods. Selecting this method allows you to input:
Origin and destination (e.g. cities, airports, ports)
Mode of transport (e.g. air, road, sea — for freight; air, rail, car — for business travel)
Weight of cargo (for freight) or number of passengers/trips (for travel)
Tip: If your cargo type and route are identical across multiple shipments, you can use the total weight rather than entering each shipment individually, the result will be the same, and it reduces the number of entries needed.
Using route-based data in exports
Conversion factors included: Exports now show the emission factor conversion factors applied, making it easier for your team and auditors to trace how figures were derived.
Market-based / location-based options: You can choose which carbon accounting methodology is reflected in exports, relevant if you need to report under GHG Protocol, RE100, or SECR.
Checking data quality: confidence scores
The KEY ESG Carbon Auditable Report includes a confidence score in the source field for each route-based entry. This score reflects how precisely the platform was able to match your input to a known route and emission factor:
99% confidence — the route was matched exactly (e.g. a recognised airport code or city pair with a precise emission factor)
50% confidence — the route could not be fully matched and was processed with a fallback or approximate factor (this typically shows as n/a in the source field)
This gives you a clear signal for where to focus your data quality checks. If you see low confidence scores in your report, review those entries and consider providing more specific route information (e.g. using IATA airport codes rather than city names for air travel).
To check confidence scores:
Go to the Reports page
Export the Carbon Auditable Report
Review the Source field — this will show the matched route and its associated confidence level
Bulk upload for air travel (Category 6)
If you are submitting air travel data via bulk upload, here is guidance on how to complete each column:
Journey field
This refers to the number of times a particular route was travelled. For example, if the London → New York route was flown 10 times, enter 10 in the Journey field. Each row represents a unique route, not a unique trip.
General guidance
Additional column-level guidance is available at the top of the data entry page for each data point. Check there first if you are unsure how to complete a specific field.
Routes marked as n/a or not detected
If a route cannot be detected by the platform (e.g. because the origin or destination is unrecognised), it will be highlighted as an error and will prevent saving. The platform does not process undetected routes — you will need to correct the entry before the submission can be saved.
FAQs
Q: What does the "Journey" field mean in the bulk upload template?
Journey refers to the count of trips on a given route. If the same route (e.g. London → New York) was travelled 10 times, enter 10 — do not create a separate row for each trip.
Q: What happens if a route is not recognised?
Unrecognised routes are flagged as errors and will prevent you from saving the submission. You will need to correct or clarify the route before proceeding. Check the confidence score in the Carbon Auditable Report to identify which entries were not fully matched.
Q: How can I check how the platform mapped my travel routes?
Go to the Reports page, export the Carbon Auditable Report, and review the Source field. This shows how each route was matched and includes the confidence score for that match.
Q: Should I use total weight or break down individual items for freight?
If the route and cargo type are the same across items, use the total weight. Breaking down by individual items does not change the emission calculation, since emission factors scale linearly with weight.
Q: Where can I find the emission factors used?
Conversion and emission factors are included in your carbon export. The Carbon Auditable Report also shows the source of each emission factor and the confidence level of the route match.
Q: Is route-based available through the API?
Yes. Route-based validation is also supported via the KEY ESG public API.
For further questions, please contact the KEY ESG support team.