Carbon Footprint Calculator API: Emission Factors and CO2e

Search thousands of scientifically vetted emission factors and calculate carbon emissions in kg CO2e for energy, fuel, travel, materials, spend and freight through the Climatiq API with your own API key, as clean rows you can export to CSV, Excel or JSON.

Climatiq is a carbon calculation API with an emission factor database built from more than 140 datasets, including EPA, BEIS (DESNZ), EXIOBASE, IEA, ecoinvent, GLEC and many national inventories. This actor wraps its emission factor search, its basic estimate, procurement and intermodal freight calculation endpoints, and its unit type and data version lookups. Use it for corporate carbon footprints (Scope 1, 2 and 3), Scope 3.1 purchased goods and services, logistics emissions under the GLEC Framework and ISO 14083, ESG reporting pipelines and product carbon accounting. Bring your own API key.

BYOK, not live tested: every route, parameter and response field comes from Climatiq's own API reference at climatiq.io/docs/api-reference, and every route was probed on 2026-10-27 with an invalid key. The actor has not been run against a live Climatiq key.

What it does

• Emission factor search: GET /data/v1/search with free text and filters for activity ID, factor ID, region (with wildcards), year, source, source dataset, category, sector, GHG Protocol scope, unit type, LCA activity, IPCC calculation method (AR4, AR5, AR6), access type and data quality flags. One row per factor with name, activity ID, factor value and unit, region, year, source, dataset, source link, scopes, constituent gases (CO2, CH4, N2O), uncertainty and data version status, paged automatically up to 500 per call.
• Activity emissions estimate: POST /data/v1/estimate/batch, 100 activities per call. Give an emission factor selector (activity ID with region, year, source and fallbacks, or a unique factor ID) and parameters for its unit type: energy (kWh, MWh, GJ, therm), weight, volume, distance, passengers over distance, weight over distance, money spent and more. Returns kg CO2e, the factor used, constituent gases and activity data. Spend based estimates can be inflation adjusted.
• Spend based procurement estimate: POST /procurement/v1/spend/batch for Scope 3.1 purchased goods and services from NACE, ISIC, NAICS, MCC or UNSPSC codes, with EXIOBASE tax, trade and transport margins, exchange rates and inflation applied.
• Intermodal freight emissions: POST /freight/v3.1/intermodal for shipments by road, rail, sea, air and inland waterway with automatic routing, giving total, hub, vehicle operation and energy provision CO2e, distance, cargo tonnes and each route leg.
• Unit types and latest data version: GET /data/v1/unit-types and GET /data/v1/data-versions.
• Citations built in: every factor and estimate row carries a citation line (source, dataset, year, region), and estimates keep the full source trail.
• Pay only for results: refused items and empty searches are recorded as a free row that says why, never charged.

When the data version input is empty, the actor asks Climatiq for the latest release and uses its caret form (such as ^38), which the search and activity ID selectors require.

How to use it

1. Get a Climatiq API key: sign up at climatiq.io, open API Toolkit, API Keys and create one. The free community plan allows a limited number of non-commercial calls; paid plans unlock commercial use and more features.
2. Paste it into the API key field, or set the DATA_API_KEY environment secret.
3. Pick a mode. Search first to find the activity ID and unit type you need, then estimate with it.
4. Download the dataset as JSON, CSV or Excel, or connect it to your workflow through the Apify API, webhooks or integrations.

Input

Field	Modes	Notes
mode	all	searchFactors, estimate, procurement, freight, unitTypes, dataVersions
query, activityId, factorId, region, year, source, sourceDataset, category, sector, scope, unitType, sourceLcaActivity, calculationMethod, accessType, allowedDataQualityFlags	search	Climatiq's documented search filters
estimates	estimate	JSON array of estimate request bodies
spendItems	procurement	JSON array of procurement request bodies
shipments	freight	JSON array of freight request bodies
dataVersion	search, estimate	such as ^38; empty means the latest release
maxResults	all	most rows returned and charged, default 100
requestsPerMinute	all	pacing, default 120
apiKey	all	your Climatiq API key, stored as a secret

Example activity estimate input:

{
    "mode": "estimate",
    "estimates": [
        {
            "emission_factor": { "activity_id": "electricity-supply_grid-source_residual_mix", "region": "DE", "region_fallback": true },
            "parameters": { "energy": 1000, "energy_unit": "kWh" }
        },
        {
            "emission_factor": { "activity_id": "metals-type_steel_section" },
            "parameters": { "weight": 100, "weight_unit": "kg" }
        }
    ]
}

Output

One row per factor or estimate. Example estimate row (trimmed):

{
    "mode": "estimate",
    "recordType": "estimate",
    "query": "activity 2",
    "found": true,
    "co2e": 292.1894413,
    "co2eUnit": "kg",
    "co2eCalculationMethod": "ar5",
    "activityValue": 100,
    "activityUnit": "kg",
    "emissionFactorId": "88d331fb-1a4a-8342-a585-78e1bde3c57f",
    "activityId": "metals-type_steel_section",
    "name": "Steel section",
    "category": "Metals",
    "source": "OEKOBAUDAT",
    "sourceDataset": "OEKOBAUDAT 2024-I",
    "citation": "Source: OEKOBAUDAT, OEKOBAUDAT 2024-I (2023, DE)",
    "year": 2023,
    "region": "DE",
    "constituentGases": { "co2e_total": 292.1894413, "co2": null, "ch4": null, "n2o": null },
    "request": { "emission_factor": { "activity_id": "metals-type_steel_section", "data_version": "^38" }, "parameters": { "weight": 100, "weight_unit": "kg" } },
    "record": { "...": "the full Climatiq answer" },
    "note": null
}

Search rows add factor, unit, unitType, sector, sourceLink, scopes, uncertainty, description, dataQualityFlags and dataVersionStatus. Procurement rows add taxMargin, tradeMargin, transportMargin, inflationApplied and sourceTrail. Freight rows add hubEquipmentCo2e, vehicleOperationCo2e, vehicleEnergyProvisionCo2e, distanceKm, cargoTonnes and legs.

Citing emission factor sources

Climatiq's terms ask you to cite the sources of the emission factors you use. Every row carries a ready citation line built from the factor's source, dataset, year and region, and search rows also carry the publisher's sourceLink. Keep that line next to any figure you report. Freight results may contain OpenStreetMap data, which Climatiq asks you to attribute, for example "May contain information from OpenStreetMap".

Pricing

Pay per event, only for rows that carry a real Climatiq result:

Event	Price
Emission factor (search result)	$0.005
CO2e emissions estimate (activity or spend item)	$0.01
Freight shipment emissions	$0.02
Unit type or data version	$0.005

Your Climatiq plan and its call quota apply on top. Each batch element counts as one Climatiq API call.

FAQ

What is the Climatiq API?

Climatiq is a Berlin based carbon calculation API. It serves an emission factor database from more than 140 public and premium datasets and calculation endpoints that multiply activity data by the right factor to give kg CO2e, for energy, travel, freight, procurement and product footprints.

Do I need my own Climatiq API key?

Yes. This actor is bring your own key: it calls Climatiq with your key and your plan. Without a key the run ends straight away with a message saying how to get one, and nothing is charged.

How do I find the right emission factor?

Run the emission factor search with a few words (such as diesel, hotel stay or grid electricity) plus a region and year. Each row gives the activity ID, unit type and source. Use that activity ID and unit type in the activity estimate mode, or use the unique factor ID to pin one exact factor for audit purposes.

How do I calculate Scope 2 electricity emissions?

Use the activity estimate mode with an electricity activity ID, such as electricity-supply_grid-source_residual_mix or a location based grid mix, a region code and {"energy": 1000, "energy_unit": "kWh"}. Set region_fallback to true to fall back to a larger region if the exact one has no factor.

How do I calculate Scope 3.1 purchased goods emissions from spend?

Use the spend based procurement mode with an industry classification code (NACE, ISIC, NAICS, MCC or UNSPSC), the spend year, the country of production and the amount and currency. Climatiq applies EXIOBASE basic price margins, exchange rates and inflation.

How do I calculate shipping and logistics emissions?

Use the intermodal freight mode with a route of locations and legs (road, rail, sea, air or inland waterway) and the cargo weight. Climatiq follows the GLEC Framework and returns per leg results.

Why is the factor value empty in my search results?

Climatiq returns the raw factor value only on plans with that add on; otherwise it is null and you calculate with the estimate mode instead. Premium datasets also need a separate license.

What do I pay?

The actor's per row price above, plus whatever your Climatiq plan charges. The community plan is free for a limited number of non-commercial calls.

Keyword map

carbon footprint calculator API, emission factor database, CO2e calculator, carbon emissions API, GHG emissions calculation, Scope 1 2 3 emissions, Scope 3.1 spend based emissions, freight emissions calculator, GLEC ISO 14083, EXIOBASE, EPA emission factors, DEFRA BEIS emission factors, electricity grid emission factors, ESG carbon accounting data.

Routes and verification

Mode	Route	Source	Probe with invalid key (twice)
Emission factor search	GET /data/v1/search	API reference, Search	401 Your authentication token was not valid; /data/v1/searchx 404
Activity emissions estimate	POST /data/v1/estimate/batch	API reference, Basic Estimate and Batch Endpoints	401; /data/v1/estimate/batchx 404
Spend based procurement	POST /procurement/v1/spend/batch	API reference, Procurement	401; /procurement/v1/spendx 404
Intermodal freight	POST /freight/v3.1/intermodal	API reference, Freight v3.1	401; /freight/v9.9/intermodal 404
Unit types	GET /data/v1/unit-types	API reference, Unit Types	401; /data/v1/unit-typez 404
Latest data version	GET /data/v1/data-versions	API reference, Data Versions	401

The key goes in an Authorization: Bearer header and never in a URL or a log line. Private factor management, the Mapping Agent, PCF, travel and energy endpoints are not wrapped.

Licensing and data use

This actor works only with your own Climatiq API key, and your agreement with Climatiq applies. Use the output inside your own product or analysis rather than reselling it, keep to the non-commercial limit of the community plan, and cite the emission factor sources you use. Premium datasets carry their own license terms. This actor is not affiliated with or endorsed by Climatiq GmbH.