Query emission factors
Search and filter emission factors across DEFRA, EPA, ADEME and Ember. Pass source=list to get the catalogue of available sources and years instead of factor rows.
Query parameters
Data source, or "list" to enumerate available sources/years.
Publication year. Availability depends on source: DEFRA 2023-2026, EPA 2023-2025, ADEME 2024 only, Ember 2025 only.
GHG Protocol scope filter, e.g. "1" or "1,2" (comma-separated). Matches "Scope 1", "1", etc.
Free-text match against the factor's category hierarchy (levels.level_1..level_4) and activity name, e.g. "fuels", "electricity", "waste".
Free-text search across the entire factor record, e.g. "natural gas", "aviation".
Rows to return. Capped at 500 regardless of the value passed.
Pagination offset.
Response
Matching factors, or the source/year catalogue when source=list.
Example response
{
"data": [
{
"scope": "Scope 1"
}
]
}