This site’s footprint
A figure without its method is worth nothing. Here are both.
Recalculated automatically every time the site is published.
What is measured
The transferred weight is measured, not estimated: the site generator compresses every file exactly as the server will send it, and adds up the bytes. A first visit to the home page transfers 69.0 KB — the page, the stylesheet, the script and the icon. Later visits transfer only the page, 4.7 KB, the rest already being in the browser’s cache.
This site loads nothing else: no remote font, no library, no background image, no video, no tracker. What is not loaded costs nothing — the one lever that is not up for debate.
What is estimated
Converting bytes into energy cannot be measured from a website: it depends on the network used, the visitor’s device and the data centre. We apply the factors of the Sustainable Web Design model (version 4), which splits consumption across three segments, per gigabyte transferred:
network 0.059 kWh/GB · data centre 0.055 kWh/GB · visitor device 0.080 kWh/GB.
That is, for a first visit: 13.7 mWh.
The associated emissions then depend on the electricity mix. The site is hosted in France; we use 56 gCO₂e/kWh, the French mix in the ADEME Empreinte database. A first visit therefore represents 0.77 mg, and a subsequent page 0.05 mg.
What these figures do not say
They do not cover the manufacturing of equipment — servers, network, your own device — which, over the hardware’s lifetime, weighs far more than the electricity used. No public model allows it to be attributed honestly to a page view.
Nor do they measure your visit: this site does not count its visitors. The values above describe one page served, not what the site consumes overall — since we do not know how many times it is read.
Finally, the conversion factors are global averages, revised regularly. They give a sound order of magnitude, not accounting to the milligram.
For scale
The median web page today weighs 2.6 MB (HTTP Archive). This one is roughly 40 times lighter.
The server itself drops to zero instances when nobody is reading: it consumes nothing between visits. The same principle, applied to infrastructure — do not run what nobody needs.