Did you know that your website and digital assets have a carbon footprint?

Do you know your websites CO2 output?

If the answer to either of these is no, then don’t worry as you’re one of many companies that would answer the same as you. If you answered yes, maybe we can help you to bring your footprint down.

Here at Bnode Ltd, we are leading the way in sustainable web development by considering these factors when working with our clients. Not only is it ‘the right thing to do’, but there are so many benefits of being ethically minded and bringing these morals into your business’ websites and marketing material.

If you are on your journey to net zero, or are already claiming to be net zero but haven’t considered these outputs, then Bnode Ltd are here to work with you on your sustainable path.

So what are some of the benefits other than it being ‘the right thing to do’?

“Businesses that act sustainability build 5.7% more trust with customers and employees. Although underlying factors like supply chain issues and inflation can undermine these efforts.” Source: Edelman.com

Your website is your digital shop window. If you practice what you preach and are aware that your digital assets contribute to your journey to net zero, you can help to prevent any trust erosion by showing that you are ethically sound.

 “Over 66% of consumers say they would spend more for a product if it came from a sustainable brand.” Source: Nielsen report

The benefits of customer sales for a business that shows strong environmental considerations are massive.

 “Over 81% of global consumers feel strongly that companies should help improve the environment.” Source: Nielsen report

It’s not just about the products or services that you may supply. A strong marketing plan and PR strategy that can be reflected on your website about your digital impact awareness can take you to new levels of customer satisfaction and growth.

Your website SEO rankings are directly affected by the speed of your website. Source: Google’s pagespeed.web.dev

A strong contributing factor to this is the file size of each image, video, script and plugins. When designing with sustainable web development in mind from the ground up, Bnode consider the energy usage when your website pulls these assets down from a server to display on a user’s machine. Therefore a reduction in CO2 output also contributes to enhanced SEO rankings.

And there’s so much more…

What are some typical examples of a website’s CO2 output?

(Figures below are based on an average of 10,000 visits per month with a ratio of 40% new visitors and 60% returning visitors, though many websites have more than that & vary on their ratios.)

Less than 0.5g output per first visit

Bnode’s website has been created sustainably, with techniques to reduce its carbon impact. It produces just 0.345g of CO2 per page view and is powered by renewable energy. With approximately 10,000 views per month this is the equivalent to driving 2.45 miles in an electric car, or watching 2 hours of Netflix (in HD).

If your website is generating less than 0.5g of CO2 per page visit then you are doing amazingly with your sustainable web development journey. You can always look towards other elements to assist with your low emission digital assets such as checking that your website is running on a server that uses renewable energy (and not just offsetting its footprint / credits.)

Between 0.51g and 1g output per first visit

With approximately 10,000 views per month this is around 6.5Kg of CO2 per month. This is the equivalent to driving 4.2 miles in an electric car, or watching 3 hours of Netflix (in HD).

Between 1.1g and 1.5 output per first visit

With approximately 10,000 views per month this is around 13.7Kg of CO2 per month. This is the equivalent to driving 9.88 miles in an electric car, or watching 6 hours of Netflix (in HD).

Above 1.51g output per first visit

These values can vary with being ‘oven’ and mount so here are a couple of examples:

With 8Kg CO2 per first visit: With approximately 10,000 views per month this is around 41Kg of CO2 per month. This is the equivalent to driving 30 miles in an electric car, or watching 17 hours of Netflix (in HD).

With 29Kg CO2 per first visit: With approximately 10,000 views per month this is around 116.7Kg of CO2 per month. This is the equivalent to driving 76 miles in an electric car, or watching 46 hours of Netflix (in HD).


What things could be done to lower a website’s CO2 output?

Below are just some initial examples of things that can be done to ensure that a website has low emissions, although there are many other techniques that can be applied to sustainable web development.


Optimising images for your website can make a large difference to their file size which directly effects the amount of downloading needed and therefore energy usage. It also affects the speed of your website and contributes to good practice in the eyes of Google.

  1. Ensure that you are exporting images in the latest web formatting. JPG, SVG, PNG, and sometimes GIF’s are much smaller than TIFF, BMP, or others.
  2. Ensure that the correct formats above are optimised versions. For example, use a JPG that has been optimised for the web and not in its maximum file size standard formatting. Anything from 30% to 60% compression can have very little effect visually than 100%.
  3. Ensure that the DPI is set to 72. When printing, images are usually set to 300 DPI or more which is not required for digital screen output.
  4. Use a tool to compress the images further if possible. ‘TinyPNG’ for example is a free online tool that compressed PNG files even further to save file size.
  5. If your images have wording on them, can this be excluded from the image and be created by the font on the website? Not only can this save of sizes of images needed, it is also great practice for ensuring website accessibility standard for users with page readers or anything that changes the font size and colours.


Calling external scripting can increase the page weight dramatically. This can be anything from the fundamental coding used to create your website (if you purchased a template for WordPress for example) to 3rd party plugins, social connections (Facebook, Twitter, etc), and analytical software (Google Analytics etc.)

  1. In an ideal world do not purchase a template to build your website. They may have the initial design and layouts but they are usually coded quickly and without care, simple prioritizing the aesthetics and speed of production over quality. All of those variations of the header, page structure, and footer are all in the code even if you don’t use them. Build your own website or template using the best and most considerate ethical standards.
  2. Consider the best practices when using scripting such as Javascript to create elements of your website as and when needed. Before launching your website ‘Minify’ the scripting too. Javascript is commonly minfied to compress the coding as much as possible after production.
  3. Try not to use to many plugins from 3rd parties to make your website look and work how you would like it. These can be again messy coding and it is always better to use standard scripting such as HTML to achieve the same User Experience (UX) if possible.
  4. Do you need that additional coding? Remember that websites do not have to have elements moving around for the sake of it. Just because you can have the text spinning in, is it good UX practice for accessibility purposes and page weight / load speeds?
  5. Ensure that your scripting does not have any errors in it and is coded efficiently. Sometimes although something can work on a website, it doesn’t mean that the scripting hasn’t been fragmented across the page or is within many different files. This can lead to unnecessary work as the browser gathers the required elements or looks over/reloads elements each time if it needs them.


Using a web standard front is ideal but is sometimes not possible to follow brand guidelines. If you are having to load in a specific font, do so in the correct method and ideally by using a recognised source such as Google or Adobe Fonts.


‘Lazy load’ images if possible and use a content delivery network (CDN). A CDN is a group of servers that are located across the globe and provide a cached version of your website to users. This prevents images from having to be downloaded from servers that are far away and multiple times, thus reducing weight on servers and CO2 outputs, along with the added benefit of speeding up your website for its users.

Also consider your website hosting platform. Are you using a provider that provides 100% renewable energy to power its datacenters? Are you using someone that claims to be doing just that, but they are actually offsetting their CO2 output with credits?

Are there other things that can be done to be digitally sustainable?

Yes, many! In fact, far too many to mention in one article. This is why Bnode are experts in ethical, sustainable web development as we see the time for digital marketing being united with sustainability being right now.

If you’re interested to learn more about the services that we provide at Bnode Ltd and how we can build an ethically strong digital presence for your company, please get in touch with us today. We would love to hear from you.

If you have an accountant, they should be your first stop for business advice. If you don’t have an accountant or they can’t help, BuBul has a wide range of experts available. For more advice, contact our expert* Chris at https://bnode.co.uk/ or on LinkedIn.

*We’ve picked experts we know and trust who are good at what they do. All of them will give you at least an extra 30 minutes free advice if you contact them and would then charge their normal prices. They don’t pay to be on BuBul and don’t give us any money from anything they earn as an expert.