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Every website visit causes a CO2 emission of approximately 0.8g CO2. This may not appear to be a lot, but the cumulative effect is significant.

0.8g CO2 for a single page view may not seem much. But if all 8 billion people were to visit a site, it would result in CO2 emissions of 6,400 tonnes. That's roughly equivalent to 3,200 intercontinental flights (return trips) over 8,000km in economy class. With the second click, it's 6,400 flights, with the third, 9,600, and so on.

Assuming that a tree can absorb about 20kg of CO2 per year on a global average, it would take 320,000 trees to offset the CO2 emissions of a worldwide page view. Not to forget that all is released again when the trees die and decompose.

All for a single page, without even knowing if it was read or just clicked away.

Analysis Tools

Anyone wanting to know the CO2 footprint of a website can find out using one of the leading CO2 analysis services. Simply enter the address and you'll know its footprint. It's a matter of seconds.

Overview of CO2 Analysis Services

Page Bloat

The first webpage in 1991 was 5 KB. Today, they average 2500 KB. The trend is upward. The term Page Bloat stands for web pages with more and more images, videos, and interactive or immersive worlds. How can the CO2 emissions associated with them be reduced?

Decarbonisation Strategies


Conventional platforms like WordPress, Joomla, or TYPO3 have a fundamental problem. They are database-driven systems, i.e., every page call requires resource-intensive interactions with a database. This consumes additional energy and causes corresponding CO2 emissions. Modern methods do without databases and generate pages that can be retrieved immediately and with low emissions. How can both methods be sensibly combined?

Plugins and Templates (Themes)

A platform is usually operated with Plugins and Templates (Themes), which allow for the design of a website and the extension of its functionalities. For most platforms, there is a wide selection available. The variety has many advantages, but in terms of web ecology, it has a major disadvantage. The free combination of core, plugins, and templates results in bloated and erroneous code, leading to high CO2 emissions when accessing pages. With the W3C Validator, errors can be identified and appropriate measures can be taken.


Fonts leave a terrible CO2 footprint. They cause a significantly higher emission than the text they serve. How can the CO2 emission of a font be reduced?

Sustainable Fonts

Energy Efficiency Classes

Energy efficiency classes are a given in all technology sectors, except on the Web. They allow for the assessment of the ecological sustainability of technologies and making climate-friendly decisions. Why are there no energy efficiency classes for web technologies, the fastest-growing technology sector? Wouldn't they be especially important here? How can energy efficiency classes for web technologies be defined and enforced?

The Problems
Initial Solutions
Energy Efficiency Classes for Web Tools

Web Analytics

Web analytics for capturing user behavior are resource-intensive processes, with corresponding CO 2 emissions. They are conducted in real-time with complex solutions (Google Analytics, Matomo, or other statistical tools). However, they can also be performed resource-efficiently using the log files provided by every server. In this way, not only are data protection issues avoided, but the CO2 emissions associated with real-time capturing are also prevented. What solutions exist to evaluate user behavior in a resource-efficient manner?

We combine various methods to effectively reduce the CO2 emissions of a page view. Website Carbon and Ecograder rarely identify more than an initial emission of 0.02g for websites created using a process. That's a reduction of 97.5 percent.

The energy efficiency of our solutions is unmatched.