openapi: 3.0.3
info:
  title: IQAir AirVisual Cities API
  description: The IQAir AirVisual API provides real-time and forecast air quality and weather data worldwide. It offers endpoints for listing supported countries, states, and cities, retrieving air quality data for specific locations or nearest stations, and ranking cities by air quality index.
  version: 2.0.0
  contact:
    name: IQAir
    url: https://www.iqair.com
servers:
- url: https://api.airvisual.com/v2
  description: IQAir AirVisual API v2
security:
- apiKey: []
tags:
- name: Cities
  description: List supported cities and retrieve city air quality data
paths:
  /cities:
    get:
      tags:
      - Cities
      summary: List supported cities
      description: Returns a list of all supported cities within a specified state and country.
      operationId: listCities
      parameters:
      - name: key
        in: query
        required: true
        description: Your API key
        schema:
          type: string
      - name: state
        in: query
        required: true
        description: State name
        schema:
          type: string
        example: California
      - name: country
        in: query
        required: true
        description: Country name
        schema:
          type: string
        example: USA
      responses:
        '200':
          description: Successful response
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/CitiesResponse'
        '400':
          description: Bad request
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
        '401':
          description: Unauthorized
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
        '429':
          description: Rate limit exceeded
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
  /city:
    get:
      tags:
      - Cities
      summary: Get city air quality data
      description: Returns air quality and weather data for a specified city, including current conditions, forecasts, and history.
      operationId: getCity
      parameters:
      - name: key
        in: query
        required: true
        description: Your API key
        schema:
          type: string
      - name: city
        in: query
        required: true
        description: City name
        schema:
          type: string
        example: Los Angeles
      - name: state
        in: query
        required: true
        description: State name
        schema:
          type: string
        example: California
      - name: country
        in: query
        required: true
        description: Country name
        schema:
          type: string
        example: USA
      responses:
        '200':
          description: Successful response
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/CityDataResponse'
        '400':
          description: Bad request
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
        '401':
          description: Unauthorized
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
        '429':
          description: Rate limit exceeded
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
  /nearest_city:
    get:
      tags:
      - Cities
      summary: Get nearest city air quality data
      description: Returns air quality data for the nearest city based on IP geolocation or provided GPS coordinates.
      operationId: getNearestCity
      parameters:
      - name: key
        in: query
        required: true
        description: Your API key
        schema:
          type: string
      - name: lat
        in: query
        required: false
        description: Latitude coordinate. If not provided, IP-based geolocation is used.
        schema:
          type: number
          format: double
        example: 34.0522
      - name: lon
        in: query
        required: false
        description: Longitude coordinate. If not provided, IP-based geolocation is used.
        schema:
          type: number
          format: double
        example: -118.2437
      responses:
        '200':
          description: Successful response
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/CityDataResponse'
        '400':
          description: Bad request
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
        '401':
          description: Unauthorized
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
        '429':
          description: Rate limit exceeded
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
components:
  schemas:
    CitiesResponse:
      type: object
      properties:
        status:
          type: string
          example: success
        data:
          type: array
          items:
            type: object
            properties:
              city:
                type: string
                description: City name
    Pollution:
      type: object
      properties:
        ts:
          type: string
          format: date-time
          description: Timestamp
        aqius:
          type: integer
          description: AQI value based on US EPA standard
        mainus:
          type: string
          description: Main pollutant for US AQI (p2=PM2.5, p1=PM10, o3=Ozone, n2=NO2, s2=SO2, co=CO)
        aqicn:
          type: integer
          description: AQI value based on China MEP standard
        maincn:
          type: string
          description: Main pollutant for Chinese AQI
        p2:
          $ref: '#/components/schemas/PollutantUnit'
        p1:
          $ref: '#/components/schemas/PollutantUnit'
        o3:
          $ref: '#/components/schemas/PollutantUnit'
        n2:
          $ref: '#/components/schemas/PollutantUnit'
        s2:
          $ref: '#/components/schemas/PollutantUnit'
        co:
          $ref: '#/components/schemas/PollutantUnit'
    Current:
      type: object
      properties:
        weather:
          $ref: '#/components/schemas/Weather'
        pollution:
          $ref: '#/components/schemas/Pollution'
    Forecast:
      type: object
      properties:
        ts:
          type: string
          format: date-time
          description: Timestamp
        aqius:
          type: integer
          description: AQI value based on US EPA standard
        aqicn:
          type: integer
          description: AQI value based on China MEP standard
        tp:
          type: number
          description: Temperature in Celsius
        tp_min:
          type: number
          description: Minimum temperature in Celsius
        pr:
          type: number
          description: Atmospheric pressure in hPa
        hu:
          type: number
          description: Humidity percentage
        ws:
          type: number
          description: Wind speed in m/s
        wd:
          type: number
          description: Wind direction as angle
        ic:
          type: string
          description: Weather icon code
    CityData:
      type: object
      properties:
        city:
          type: string
          description: City name
        state:
          type: string
          description: State name
        country:
          type: string
          description: Country name
        location:
          $ref: '#/components/schemas/GeoLocation'
        current:
          $ref: '#/components/schemas/Current'
        forecasts:
          type: array
          items:
            $ref: '#/components/schemas/Forecast'
        history:
          type: object
          properties:
            weather:
              type: array
              items:
                $ref: '#/components/schemas/Weather'
            pollution:
              type: array
              items:
                $ref: '#/components/schemas/Pollution'
    ErrorResponse:
      type: object
      properties:
        status:
          type: string
          example: fail
        data:
          type: object
          properties:
            message:
              type: string
              description: Error message
    CityDataResponse:
      type: object
      properties:
        status:
          type: string
          example: success
        data:
          $ref: '#/components/schemas/CityData'
    PollutantUnit:
      type: object
      properties:
        conc:
          type: number
          description: Pollutant concentration
        aqius:
          type: integer
          description: AQI value based on US EPA standard
        aqicn:
          type: integer
          description: AQI value based on China MEP standard
    Weather:
      type: object
      properties:
        ts:
          type: string
          format: date-time
          description: Timestamp
        tp:
          type: number
          description: Temperature in Celsius
        pr:
          type: number
          description: Atmospheric pressure in hPa
        hu:
          type: number
          description: Humidity percentage
        ws:
          type: number
          description: Wind speed in m/s
        wd:
          type: number
          description: Wind direction as angle (N=0, E=90, S=180, W=270)
        ic:
          type: string
          description: Weather icon code
    GeoLocation:
      type: object
      properties:
        type:
          type: string
          description: GeoJSON type
          example: Point
        coordinates:
          type: array
          items:
            type: number
            format: double
          description: Longitude and latitude coordinates
          example:
          - -118.2437
          - 34.0522
  securitySchemes:
    apiKey:
      type: apiKey
      in: query
      name: key
      description: API key passed as a query parameter.