Skip to content

How does the Green Web Check work?

The Green Web Check is a tool that allows you to find out whether a specific website is being hosted by a verified green provider or not.

When providers become verified with us they’re listed in our Green Web Dataset. Along side capturing the evidence they submit to prove their green claims, we maintain a list of all the IP addresses assigned to them.

Showing a green result

When we look up a domain, we consult DNS records that eventually resolve to an IP address that a server is reachable at. In our database we associate IP addresses with a given organisation three different ways outlined in the diagram below – by IP addressby IP Range, or by Autonomous System Number (ASN)

For the most part, we are relying on information stored in DNS records added by an organisation that has the control over a domain, and then we are checking that against information previously shared with us. 

So, when someone runs a green web check against a given domain, we base the ‘green’ / ‘not green’ result on our ability to link a domain to an IP address shared with us.

If the organisation associated with that IP address has shared the necessary sustainability data with us, then we can establish a link between the domain and the organisation’s sustainability info allowing us to serve a ‘green’ result.

Showing a grey result

When an organisation uses public IP addresses that we cannot link to supporting evidence of accounting for the emissions from the underling infrastructure, we show a result as grey.