How we measure website carbon footprints

1. Measure the amount of data your website transfers

Our website carbon footprint calculator starts by measuring how much data is transferred when different pages on your website are loaded.

We measure multiple pages for a more accurate result

2. Check your website hosting

The calculator next looks at the web hosting your website uses and checks to see if it's using renewable energy on the Green Web Foundation Directory.

3. Calculate the total amount of electricity used

Next we take your website's traffic and calculate the total amount of electricity used by your website over a set period.*

There are more than 8.5 BILLION google searches per day

4. Check that against the latest UK carbon intensity data

Our calculator outputs the amount of CO2e based on the amount of electricity required and the latest data for the intensity of UK electricity generation.**

Our calculator uses data for the UK's energy CO2 intensity

5. Show the equivalent CO2 for offset

To help you visualise the impact of your website and the required offset, the calculator shows the impact normally based on the CO2 absorption of the average UK tree.***

*Can't provide website traffic stats? We'll use an estimate of your website traffic but the calculation will be less accurate.

**We frequently update the CO2e energy generation data with the latest results to reflect the UK's move toward more sustainable energy generation.