# Does Dockflow return the CO2 emission value in the API output, and where do I find it?

**URL:** <https://community.dockflow.com/t/does-dockflow-return-the-co2-emission-value-in-the-api-output-and-where-do-i-find-it/115>\
**Category:** How-to Q&A\
**Tags:** area-api-integration\
**Created:** [November 6, 2026, 2:53pm UTC](https://community.dockflow.com/t/does-dockflow-return-the-co2-emission-value-in-the-api-output-and-where-do-i-find-it/115 "2026-11-06T14:53:11Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![dockflow](https://community.dockflow.com/letter_avatar_proxy/v4/letter/d/a9a28c/32.png) [@dockflow](https://community.dockflow.com/u/dockflow)\
**Post date:** [November 6, 2026, 2:53pm UTC](https://community.dockflow.com/t/does-dockflow-return-the-co2-emission-value-in-the-api-output-and-where-do-i-find-it/115/1 "2026-11-06T14:53:11Z")

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Yes. Dockflow returns CO2 emission data in the API record. Look for the `carbon_emissions` field, which the documentation describes as CO2 emission data for the shipment route.

Polling returns records in the `data` array. Webhooks send one record in `data`, and that record is the same as polling with the default fields, which include `shipment`. Both modes return the same record.

Inside `carbon_emissions`, read `distance_km` for route distance in kilometers and `co2_emissions_kg` for total CO2 in kilograms. The total is Well-to-Wheel, made up of Tank-to-Wheel plus Well-to-Tank. `ttw_kg` is the Tank-to-Wheel part, meaning direct fuel combustion. The field is null when the value has not yet been calculated.

So your integration should read the CO2 value from the `carbon_emissions` field in each record. If that field is null, no calculated CO2 value is available yet.

**Example**  
For a general ocean shipment, the record can show a route distance in `distance_km` and a total CO2 value in `co2_emissions_kg`. The `ttw_kg` value is the direct combustion part. Your integration reads these from `carbon_emissions` in each polling or webhook record. If `carbon_emissions` is null, the calculation has not been done yet.