The internet is a system that was introduced over 30 years ago and has taken over the world since then. Connecting over 5 billion people is possible thanks to the global scale that the internet operates at. While the advantages are unmistakable, we must also acknowledge that the internet is a large contributor to the emission of greenhouse gasses. The footprint of the individual user might be relatively small, but as the number of users is only expected to grow, we must find a way to make the internet more sustainable. In this thesis we explore the state of sustainable web design from three different perspectives: academic, development and end user. Based on academic publications we create a catalogue of nine green web patterns that have empirically been shown to reduce the energy consumption. Secondly, we analyse developer communication on GitHub to see what green patterns are being used in practice. Our results show that there is very limited conversation about the implementation of green patterns, whereas for mobile app development the use of green patterns is more common. Lastly, we take on the end user's perspective and audit the websites of universities to find a relation between a sustainable reputation and a sustainable website. For the audition of websites we create a Google Lighthouse plugin specifically to test sustainability. We find a significant difference between the websites from the group of most sustainable universities and the group of least sustainable universities. The main takeaway of this thesis is that there is a lot of room for improvement to make websites more sustainable. A lack of awareness found from all three perspectives is currently a bottleneck for wider adoption of green patterns. We argue that the availability of development tools with built-in sustainability features could increase awareness and adoption of sustainable web design.