openapi: 3.1.0
info:
  title: Climatiq Autopilot Estimate API
  version: '3'
  description: Climatiq is a carbon emissions calculation API that gives developers programmatic access to a curated database of emission factors and to purpose-built calculation endpoints. The API exposes search over the factor catalog and a family of estimation endpoints for activity-based and spend-based calculations across travel, freight, energy, cloud computing, procurement, and CBAM workflows. Authentication uses an API key sent as a Bearer token in the Authorization header. Responses are JSON with deterministic emission outputs in CO2e (kg) plus the underlying factor metadata.
  contact:
    name: Climatiq Support
    url: https://www.climatiq.io/support
  license:
    name: Climatiq Terms of Service
    url: https://www.climatiq.io/legal/terms
servers:
- url: https://api.climatiq.io
  description: Climatiq Production API
security:
- bearerAuth: []
tags:
- name: Estimate
  description: Activity-based emission estimation.
paths:
  /data/v1/estimate:
    post:
      operationId: estimateEmissions
      summary: Estimate emissions for an activity
      description: Calculates CO2e emissions by combining a selected emission factor (via activity_id or emission_factor object) with caller-supplied activity parameters such as energy used, distance, money spent, or weight moved.
      tags:
      - Estimate
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/EstimationRequest'
      responses:
        '200':
          description: Calculated emission estimate.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/EstimationResponse'
components:
  schemas:
    EstimationResponse:
      type: object
      properties:
        co2e:
          type: number
        co2e_unit:
          type: string
          example: kg
        co2e_calculation_method:
          type: string
        co2e_calculation_origin:
          type: string
        emission_factor:
          type: object
        constituent_gases:
          type: object
          properties:
            co2:
              type: number
            ch4:
              type: number
            n2o:
              type: number
        activity_data:
          type: object
    EstimationRequest:
      type: object
      required:
      - emission_factor
      - parameters
      properties:
        emission_factor:
          type: object
          properties:
            activity_id:
              type: string
            data_version:
              type: string
            region:
              type: string
            year:
              type: integer
            source:
              type: string
        parameters:
          type: object
          additionalProperties: true
  securitySchemes:
    bearerAuth:
      type: http
      scheme: bearer
      bearerFormat: API Key