Breathe London API access

For developers who would like to embed the Breathe London sensor information directly into tools or sites, you can request API access through the form below.

API access request 

We ask for information about who and how the API will be used so that we can understand the impact of Breathe London and communicate any changes to the API to you in the future. By submitting the form you agree to the API terms of use. After registering we will provide you with an API key to access the sensor data.

Thank you for requesting access to the Breathe London API.
Once your request has been reviewed and approved you will be emailed details of your API key.

It looks like you’ve already signed up.
If you haven’t received your API key, please use the contact form below to get in touch.

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Breathe London API Terms of Use

Effective Date: 23 June 2025

These Terms of Use (“Terms”) govern your access to and use of the Breathe London API (“API”), provided by the Greater London Authority (GLA) and its partners (“We”). By accessing or using the API, you agree to comply with these Terms.

License and Access
All data made available through the API is licensed under the UK Open Government Licence v3.0 (OGL v3). You are granted a worldwide, non-exclusive, royalty-free, perpetual license to use the data, subject to the terms of the OGL.
Attribution
You must acknowledge the source of the data by including or linking to an attribution statement,: ‘Contains Breathe London data licensed under the Open Government License v3.0’. Attribution must be clear, visible, and consistent with the requirements of the OGL. This attribution must link to the Breathe London site (https://www.breathelondon.org/).
Usage Restrictions
You agree not to:
- Use the API in any unlawful or harmful manner.
- Misrepresent the data or its source.
- Exceed usage limits or attempt to bypass rate limiting.
- Redistribute or resell the data without proper attribution and compliance with the OGL.
- Use the information i any way that implies Breathe London, the GLA or its partners endorse your use of the data.
API Keys and Security
You will be required to register for an API key. You are responsible for maintaining the confidentiality of your key and for all activity associated with its use. You will not misrepresent or mask your identity when using the API.
You will comply with all applicable law, regulation, and third party rights (including without limitation laws regarding the import or export of data or software, privacy, and local laws). You will not use the APIs to encourage or promote illegal activity or violation of third party rights. You will not violate any other terms of service with Breathe London, the GLA or its partners.
Registration and Access
Access to the Breathe London API is restricted to registered users. By registering, you agree to provide accurate and complete information, including your name, organisation, and intended use of the data. The Greater London Authority (GLA) reserves the right to approve or deny access at its discretion.
No warranty
The data is provided “as is” and may be subject to change, delay, or inaccuracy. No guarantees are made regarding its completeness, accuracy, or availability. We exclude all representations, warranties, obligations and liabilities in relation to the data to the maximum extent permitted by law. We are not liable for any errors or omissions in the data and shall not be liable for any loss, injury or damage of any kind caused by its use.
Modifications and Termination
We reserve the right to modify or discontinue the API at any time without notice. Access may be revoked if you violate these Terms or misuse the service.
Intellectual Property
While the data is licensed under OGL v3, all rights in the API software, branding, and associated intellectual property remain with the GLA or its partners.
Governing Law
These Terms are governed by the laws of England and Wales.
Contact
For questions or support, please contact: helpdesk@breathelondon.org.
For our privacy policy, please visit: https://www.breathelondon.org/privacy-policy

API Guide

API Terms of Use

Breathe London API Terms of Use

Effective Date: 23 June 2025

License and Access
All data made available through the API is licensed under the UK Open Government Licence v3.0 (OGL v3). You are granted a worldwide, non-exclusive, royalty-free, perpetual license to use the data, subject to the terms of the OGL.
Attribution
You must acknowledge the source of the data by including or linking to an attribution statement,: ‘Contains Breathe London data licensed under the Open Government License v3.0’. Attribution must be clear, visible, and consistent with the requirements of the OGL. This attribution must link to the Breathe London site (https://www.breathelondon.org).
Usage Restrictions
You agree not to:
- Use the API in any unlawful or harmful manner.
- Misrepresent the data or its source.
- Exceed usage limits or attempt to bypass rate limiting.
- Redistribute or resell the data without proper attribution and compliance with the OGL.
- Use the information i any way that implies Breathe London, the GLA or its partners endorse your use of the data.
API Keys and Security
You will be required to register for an API key. You are responsible for maintaining the confidentiality of your key and for all activity associated with its use. You will not misrepresent or mask your identity when using the API.
You will comply with all applicable law, regulation, and third party rights (including without limitation laws regarding the import or export of data or software, privacy, and local laws). You will not use the APIs to encourage or promote illegal activity or violation of third party rights. You will not violate any other terms of service with Breathe London, the GLA or its partners.
Registration and Access
Access to the Breathe London API is restricted to registered users. By registering, you agree to provide accurate and complete information, including your name, organisation, and intended use of the data. The Greater London Authority (GLA) reserves the right to approve or deny access at its discretion.
No warranty
The data is provided “as is” and may be subject to change, delay, or inaccuracy. No guarantees are made regarding its completeness, accuracy, or availability. We exclude all representations, warranties, obligations and liabilities in relation to the data to the maximum extent permitted by law. We are not liable for any errors or omissions in the data and shall not be liable for any loss, injury or damage of any kind caused by its use.
Modifications and Termination
We reserve the right to modify or discontinue the API at any time without notice. Access may be revoked if you violate these Terms or misuse the service.
Intellectual Property
While the data is licensed under OGL v3, all rights in the API software, branding, and associated intellectual property remain with the GLA or its partners.
Governing Law
These Terms are governed by the laws of England and Wales.
Contact
For questions or support, please contact: helpdesk@breathelondon.org.
For our privacy policy, please visit: https://www.breathelondon.org/privacy-policy

The Breathe London API currently consists of two main calls:

/ListSensors

This call returns the meta-data for all Breathe London Nodes on the network as an array of JSON objects. An example object is shown below.

/ListSensors

Summary:

Lists the metadata for the specified sensor(s) in JSON format.

Description:

All parameters listed below are optional

The default behaviour with no parameters, returns metadata for all sensors.
The optional parameters can be used to filter the results to specific sensor(s).
Example calls
curl.exe -X GET "https://breathe-london-7x54d7qf.ew.gateway.dev/ListSensors" -H "Content-Type: application/json" -H "X-API-KEY: <insert API key>"
curl.exe -X GET "https://breathe-london-7x54d7qf.ew.gateway.dev/ListSensors?SiteCode=BL0001" -H "Content-Type: application/json" -H "X-API-KEY: <insert API key>"

Parameters:

SiteCode [optional | string]
Filter the results to only provide metadata for installations at this site
Borough [optional | string]
Filter the results to only provide metadata for installations within this London borough
Sponsor [optional | string]
Filter the results to only provide metadata for devices sponsored by this sponsor
Facility [optional | string]
Filter the results to only provide metadata for installations at this facility
Latitude [optional | number]
Filter the results to only provide metadata for installations within a circle centred at this location. Used in conjunction with Longitude and RadiusKM
Longitude [optional | number]
Filter the results to only provide metadata for installations within a circle centred at this location. Used in conjunction with Latitude and RadiusKM
RadiusKM [optional | number]
Filter the results to only provide metadata for installations within a circle with this radius (km). Used in conjunction with Latitude and Longitude

Example Response Object:

{
    "SiteCode": "BL0057",
    "SiteName": "St Annes RC Primary School",
    "DeviceCode": "13546",
    "InstallationCode": "120004",
    "Facility": "St Annes RC Primary School",
    "Location": {
        "type": "Feature",
        "geometry": {
            "type": "Point",
            "coordinates": [
                "51.4856300",
                "-0.1191570"
            ]
        }
    },
    "Latitude": "51.4856300",
    "Longitude": "-0.1191570",
    "Borough": "Lambeth",
    "SiteClassification": "Urban Background",
    "SensorHeightAboveGround": 2.9,
    "DistanceToKerb": 14.6,
    "SponsorName": "GLA",
    "SiteLocationType": "School",
    "StartDate": "2025-04-09T00:00:00Z",
    "EndDate": null,
    "PowerTag": "Mains",
    "SiteDescription": null,
    "SitePhotoURL": "https://www.airquality.london/image/120004.jpg",
    "SensorContract": "Vodafone"
}

/SensorData

Lists the measurement data for the specified sensor(s) in JSON format.

/SensorData

Summary:

Lists the measurement data for the specified sensor(s) in JSON format.

Description:

All parameters listed below are optional

The default behaviour with no parameters, returns observations for the latest hour for all sensors.
The optional parameters can be used to filter the results to specific sensor(s)/pollutants.
startTime and endTime parameters can be used to request a specific time period. NOTE: startTime and endTime must be used in conjunction with at least one of SiteCode, Borough, Sponsor, Facility or Latitude/Longitude/RadiusKM.

Example calls

curl.exe -X GET "https://breathe-london-7x54d7qf.ew.gateway.dev/SensorData" -H "Content-Type: application/json" -H "X-API-KEY: <insert API key>"
curl.exe -X GET "https://breathe-london-7x54d7qf.ew.gateway.dev/SensorData?SiteCode=BL0001" -H "Content-Type: application/json" -H "X-API-KEY: <insert API key>"

Parameters:

SiteCode [optional | string]
Filter the results to only return observations for this site, using the site code
Borough [optional | string]
Filter the results to only return observations for this London borough
Sponsor [optional | string]
Filter the results to only return observations for devices sponsored by this sponsor
Facility [optional | string]
Filter the results to only return observations at this facility
Latitude [optional | number]
Filter the results to only return observations within a circle centred at this location. Used in conjunction with Longitude and RadiusKM
Longitude [optional | number]
Filter the results to only return observations within a circle centred at this location. Used in conjunction with Latitude and RadiusKM
RadiusKM [optional | number]
Filter the results to only return observations within a circle with this radius (in km). Used in conjunction with Latitude and Longitude
Species [optional | string | allowed: NO2, PM25, NO2Index, PM25Index]
Filter the results to only return observations with a specific pollutant.
startTime [optional | string | format: date-time]
Filter the results to only return observations within the specified time period. Must be shorter than 366 days unless SiteCode is provided. If no startTime/endTime parameters are supplied, the results will be limited to the latest hour. Used in conjunction with endTime and at least one of SiteCode, Borough, Sponsor, Facility or Latitude/Longitude/RadiusKM
endTime [optional | string | format: date-time]
Filter the results to only return observations within the specified time period. Must be shorter than 366 days unless SiteCode is provided. If no startTime/endTime parameters are supplied, the results will be limited to the latest hour. Used in conjunction with startTime and at least one of SiteCode, Borough, Sponsor, Facility or Latitude/Longitude/RadiusKM

Example Response Object:

{
    "Species": "PM25",
    "Source": "Measurement",
    "Units": "ug.m-3",
    "SiteCode": "BL0086",
    "DateTime": "2025-04-01T00:00:00Z",
    "Duration": "PT1H",
    "ScaledValue": 5.55,
    "RatificationStatus": "P",
    "SensorContract": "Vodafone"
}

The new Breathe London programme will continue to launch through 2025. 

If you need to get in touch with the new Breathe London team, have a specific question about your air pollution sensor or on taking action on air pollution, please get in touch using the form below or call us on 020 4591 5660.

Thank you