Digital sustainability: How to cut your online carbon footprint

Using a smartphone, saving to the cloud, and searching the web have become second nature. But every click, stream and stored file uses electricity, just like switching on a light, plugging in a charger or running the air conditioning.

In today’s hyperconnected world, both individual habits and organisational activities add to the total environmental impact. Emerging technologies like AI deliver enormous value, but they also demand significant computing power and energy use.

The aim isn’t to slow down digital innovation, it’s to make it smarter, reducing waste and emissions while keeping performance high. This is the essence of digital sustainability.

What is digital sustainability?

Digital sustainability is the discipline of designing, operating and improving digital services and digital assets so they deliver the same or greater value with less environmental impact. In practice, it focuses on measuring and reducing the digital carbon footprint across websites, emails, archive storage, and the full set of digital assets you create and keep.

What counts as a digital asset?

Anything that can be created, stored or that can serve digitally that consumes storage, transfer or compute:

• Media: images, videos, audio, logos, animations.
  
  
• Documents: PDFs, decks, white papers, data sheets.
  
  
• Web/app code: HTML, CSS, JavaScript, fonts, third-party scripts.
  
  
• Data: backups, logs, analytics exports, datasets, AI model files.
  
  
• Emails and attachments: especially large threads and shared drives duplicated via inboxes.
  
  

Did you know?

Every page view has a carbon cost.

According to Website Carbon, CO₂e per web page view can range from ~0.36 g CO₂e to ~1.76 g CO₂e, depending on methodology and assumptions. 

Server emissions vary with energy use

A transparent walkthrough by GoClimate reports that per-server emissions can vary widely, ranging from approximately 160 kg CO₂e to over 1,200 kg CO₂e per year, depending on whether renewable energy is used and whether workloads run in cloud or on-premises data centres.

Emissions generated by the digital user

Clicks, minutes of browsing, video calls, and the email carbon footprint from sending, storing, and reading messages, add to the equation.

Where digital emissions sit in your GHG inventory

For most organisations, digital emissions fall within Scope 3, because the enabling infrastructure, public cloud, CDNs, telecommunications networks, SaaS and other third-party platforms, is owned and operated by suppliers.

Where an organisation runs its own data centres, the electricity consumed falls under Scope 2, while any on-site fuels (e.g., backup generators) fall under Scope 1. The elements associated with that electricity use, hardware manufacturing, logistics and end-of-life, remain within Scope 3.

How digital assets create impact

Digital assets produce emissions via three technical channels that together shape the digital carbon footprint.

• Transfer: This concerns the bytes exchanged between client and server, including data transferred (GB), page weight, third-party scripts and media formats.
  • A lower volume of transferred data reduces the energy required by networks and, consequently, website emissions.
    
    
• Storage: This refers to bytes stored in data centres and devices. Key variables include GB-months, duplication rate, retention policies and orphaned assets.
  • Effective storage management limits archive growth and the energy required to maintain it.

• Compute: This relates to compute cycles on servers and end-user devices. What matters are compute hours, region/energy source, model size and job frequency.
  • More efficient processing reduces energy demand and the associated impact.
    

Heavier assets → more bytes moved and stored → higher energy use and cost. 

The incidence of these factors varies by use case: streaming is dominated by transfer/compute; email is driven by transfer/storage; e-commerce primarily by transfer/compute (with storage); analytics and AI are compute-intensive.

The advantages of digital sustainability for organisations

Managing the digital carbon footprint is not only about responsibility, it improves user experience, brand reputation and cost efficiency while supporting credible ESG reporting for digital.

The digital sector is estimated to account for roughly 1.5–4% of global GHG emissions (frequently cited at around ~3.7%), a share comparable to or above civil aviation, which accounts for ~2.5% of global CO₂e. 

Consequently, reducing the website’s carbon emissions, through lighter pages, optimised media and efficient infrastructure,_, strengthens the organisation’s sustainability journey and can improve online visibility.

Revenue & UX experience

Light, efficient pages load faster and feel smoother. Optimising images, scripts and third-party tags makes content easier to find and quicker to use, which improves Core Web Vitals and SEO. The result is better visibility in search, lower bounce rates, and more successful checkouts, boosting both satisfaction and revenue while reducing digital emissions.

Cost & risk

Heavy, unoptimised pages waste resources and increase costs. By right-sizing workloads, removing duplicate files, and setting clear retention rules, organisations cut CDN, bandwidth and cloud spend. These practices also reduce storage waste and emissions, and make it easier to pass compliance checks, because it’s clear what’s stored, who can access it, and when it’s deleted.

Brand reputation & accessibility

Light, optimised experiences load reliably on slower connections, older devices and assistive technologies, enhancing satisfaction and brand perception. Accessibility improvements, with clean HTML, correctly sized media, and fewer decorative scripts, align with sustainability goals, reducing errors, support tickets, and overall digital carbon footprint. Over time, this builds trust through dependable, inclusive, and lower-carbon experiences.

How Green Future Project supports your digital sustainability journey

With digital sustainability now central to modern operations, GFP has partnered with Karma Metrix to help you measure, manage, report and communicate your digital carbon footprint. This covers key areas, including your websites, intranets, emails, corporate chat, video calls, cloud services, apps, and AI solutions, with tools to track progress and produce credible, standards-aligned ESG reporting.

Karma Metrix software is inspired by leading international standards such as GRI and the GHG Protocol. It uses a validated methodology with a patented algorithm to quantify website emissions (gCO₂e per visit).

With the team’s guidance, the service expands measurement beyond websites and turns findings into measurable outcomes, such as:

• Lower website emissions
  We help you reduce the grams of CO₂ per visit by optimising pages and infrastructure, often 35%+ per visit.
  
  
• Easier ESG reporting
  You get clear metrics that map to your sustainability goals and disclosures, so it’s simpler to show progress.
  
  
• Lower operating costs
  Leaner data transfer, compute and storage mean smaller CDN and cloud bills, typically around 10% savings.
  
  
• Quicker pages and smoother journeys
  Faster loads and simpler flows lift Core Web Vitals, SEO and conversion and leaner communications (links, not large files) further reduce bandwidth, storage and emissions
  

How can you communicate digital sustainability?

Regulations are raising the bar for emissions disclosure, so transparent communication of both results and progress is essential. 

As a first step in your Digital Sustainability journey, Karma Metrix’s Software measures your website’s CO₂e and awards a 'Digital Footprint Measured' Seal', certifying assessment with a patented, standards-aligned methodology. Once you implement improvements and demonstrate reductions of the digital operations, you can earn the 'Digital Energy Optimised' Seal for one year. 

Displaying these Seals on your website makes your commitment visible, credible and easy for stakeholders to verify. You can also include these results in your ESG report, citing the methodology, the period covered, intensity metrics (e.g., gCO₂e/visit), achieved reductions, and relevant Scope 3 categories, to strengthen transparency and comparability.

Digital sustainability is not a side project; it’s a practical way to make your digital estate faster, leaner, and easier to trust. With Green Future Project and Karma Metrix, you can achieve measurable reductions, turning small, routine improvements into lasting impact for your organisation and the people who use your services.