Train: Base Empreinte 🇫🇷

Calculate train travel emissions with ADEME's Base Empreinte factors, which take train type, regional context, grid or fuel, and factor year into account.

type trainmethodology BASE-EMPREINTEADEME Base Empreinte, 2025Supports audit mode

About the methodology

Base Empreinte, managed by ADEME, is a comprehensive environmental impact database that combines data from Base Carbone and Base IMPACTS. It supports environmental evaluations with multi-criteria data, including greenhouse gas (GHG) emissions and other environmental impacts.

For train travel, Base Empreinte factors in train type, location context (for example Corsica and Île-de-France), grid or fuel, and the year of the factor, so stakeholders get accurate, audit-ready emission calculations.

Sample requests

Send a quote before booking, then repeat the call with audit set to true once the booking is final. The body is otherwise identical.

{
  "expand": ["items"],
  "items": [{
    "audit": false,
    "type": "train",
    "methodology": "BASE-EMPREINTE",
    "external_reference": "test_1",
    "number_of_travelers": 1,
    "origin": "FRA",
    "destination": "NCE",
    "train_type": "tram",
    "state": "Ile-de-France",
    "country": "FR",
    "year": "2021"
  }]
}

audit_for is optional

Pass the ID of an auditable entity when you calculate on behalf of that entity. Otherwise, leave it out.

Defaults

Field	Default	Applies when
`city_type`	`population_under_250000`	No `city_type` is sent; `city_type` is used when `state` isn't provided
`state`	`Ile-de-France`	No `state` is sent
`country`	`FR`	No `country` is sent
`year`	Latest available	No `year` is sent
`train_type`	`main_line`	Only train type is passed
`number_of_travelers`	`1`	No `number_of_travelers` is sent

Request fields

typestringrequired

train

methodologystringrequired

BASE-EMPREINTE

external_referencestring

A unique identifier that links results to the requested item. Up to 128 characters.

number_of_travelersinteger

Minimum 1. Defaults to 1.

originstring

Origin location. See Origin and destination formats.

destinationstring

Destination location. Same formats as origin.

distance_in_kmnumber

Takes priority over origin and destination. If you send both, SQUAKE uses distance_in_km.

train_typeenum

One of ter, tgv, intercity, metro, tram, trolleybus, main_line. Defaults to main_line when only train type is passed.

stateenum

Supported regional specificity: "Corsica" or "Ile-de-France". Defaults to "Ile-de-France".

countrystring

ISO 3166-1 alpha-2 country code. Defaults to "FR".

yearstring

Year of the factor. Defaults to the latest available year.

city_typeenum

Used when state isn't provided. One of population_under_250000 (default) or population_above_250000.

auditboolean

Set to true to create immutable audit records for finalised calculations. Must be enabled for your account.

See every field of POST /v2/calculations in the API reference

Origin and destination formats

SQUAKE tries to resolve origin and destination whatever their format. Ideally, use:

Addresses: the Post standard.
Airports: an IATA/ICAO code (regex ^[A-Z]{3,4}$, for example "MUC").
Ports and trade locations: a UN/LOCODE (regex ^[A-Z]{2}\W?[A-Z2-9]{3}$, for example "DEHAM").
Coordinates: latitude and longitude (regex ^[-+]?\d{1,3}\.\d{1,10}\s?,\s?[-+]?\d{1,3}\.\d{1,10}$, for example "+40.712,-74.006").

UIC and provider codes

A UIC code is also a valid format for trains. If the value isn't valid, the system falls back to general, non-journey-specific emission data.

To use a UIC or provider code, send <provider>:<uic_code>, for example sncf:FRAAA. Possible provider prefixes: uic, uic8_sncf, sncf, sncf_tvs, entur, db, busbud, distribusion, flixbus, cff, leoexpress, obb, trenitalia, trenitalia_rtvt, trenord, ntv_rtiv, ntv, hkx, renfe, atoc, benerail, westbahn.

{
  "type": "train",
  "methodology": "BASE-EMPREINTE",
  "origin": "db:8011160",        // Berlin Hbf (example code structure)
  "destination": "db:8000105",   // Frankfurt (Main) Hbf (example code structure)
  "number_of_travelers": 2
}

Distance and fallback

If you send both origin/destination and distance_in_km, SQUAKE uses distance_in_km for emissions.
Invalid, unsupported or unresolvable location codes trigger a fallback to generic (non-journey-specific) factors consistent with Base Empreinte/ADEME practice.

Sample response

200 OKapplication/json

{
  "carbon_quantity": 4890,
  "carbon_unit": "gram",
  "items": [{
    "carbon_quantity": 4890,
    "carbon_unit": "gram",
    "external_reference": "test_1",
    "type": "train",
    "methodology": "BASE-EMPREINTE",
    "distance": 685.0,
    "distance_unit": "kilometer"
  }]
}

Bibliography

ADEME (2025). Base Empreinte - Données d’impacts environnementaux.
ADEME (2024). Base Carbone Methodological Guide.
ADEME (2023). Base IMPACTS & Rail emission factors — official ADEME documentation.

Train: Base Empreinte 🇫🇷

About the methodologyCopy Anchor Link

Sample requestsCopy Anchor Link

DefaultsCopy Anchor Link

Request fieldsCopy Anchor Link

Origin and destination formatsCopy Anchor Link

UIC and provider codesCopy Anchor Link

Sample responseCopy Anchor Link

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