Carbon footprint: how I measure it, and the result
When I display a “low-carbon website” badge, I want to be able to prove it. Here is my method, the actual figure for kanexio.com and how to check it yourself in two minutes. No empty promises, just measurement.
The measured figure
0.019 g of CO₂e per visit
An A+ rating on the Sustainable Web Design scale, around 95% lower than the scale’s reference average of 0.359 g per visit. Measurement dated 30 July 2026.
Measured input: 155,468 bytes transferred. Unrounded model result: 0.018816 g CO₂e.
How I measure
From transferred size to a dated estimate
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Load the page
Record the bytes actually transferred in the browser.
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Apply the model
Convert this input with CO2.js and Sustainable Web Design v4.
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Publish the context
State the page, date, estimated result and its limitations.
I load the page in a real browser and record the size actually transferred over the network, including compression. This size determines the energy used for each visit. The lighter a page, the less data needs to be transported and the less energy it consumes.
I then convert this size into grams of CO₂e using the Sustainable Web Design v4 model through the CO2.js library maintained by The Green Web Foundation. It accounts for returning visitors and browser caching. The Digital Carbon Ratings scale gives an A+ to pages estimated at 0.040 g CO₂e or less per visit.
Here I measure the homepage as the reference public entry point. This measurement does not automatically represent every page or the actual traffic distribution; each journey must be measured separately to establish an overall footprint.
Hosting and energy
kanexio.com is served through the Cloudflare network, recognised as a green hosting provider in The Green Web Foundation’s directory. Measurement tools consult this directory to check the energy source, and this gives the domain its “green” status.
I prefer to state this precisely rather than write a vague slogan: green status comes from the delivery network serving the pages, documented by Cloudflare’s public emissions inventory. You can check it yourself below.
Check for yourself
I am not asking you to take my word for it. Two independent tools let you check everything again.
The limitations of this measurement
Let’s be clear about what these figures are and are not. This is a model-based estimate, not an electricity bill accurate to the gram. A page’s size varies with traffic, caching and the visitor’s device.
I publish the homepage measurement rather than an average calculated across the whole website. This value is dated 30 July 2026 and must be measured again after a significant website change.
Why I care about it
A lightweight website uses fewer resources and is also faster. Eco-design and performance go together: less data to load means less energy spent, but also a website that displays quickly, ranks better and is easy to navigate.
That is exactly what I aim to build. The low-carbon badge is not a marketing claim attached afterwards; it is a direct consequence of how I work.
Last measurement: 30 July 2026.
A fast, efficient website that converts?
It is the same approach. Let’s discuss your project, with an initial conversation and no obligation.
