January 4, 2020

Calculating my family’s carbon footprint

Short version: I used 4 different calculators to try and get an understanding of how big my family’s carbon footprint is so that I can buy some carbon offsets. I got wildly differing results ranging from 14.1 tonnes of CO2 for my family up to 32.4 tonnes for just me.

WWF carbon calculatorWWF carbon calculator

Calculator 1: WWF - https://footprint.wwf.org.uk

This is a personal carbon calculator rather than a family/household calculator, went into quite a lot of detail and very easy to use. Only thing that I couldn’t answer properly was around the type of heating fuel we use, but that’s because we live in a new area which uses shared hot water from a central point of production. It also advised me that the 2020 target impact for carbon is 10.5 tonnes.

My results were 32.4 tonnes (309% of target) against what looked like around 10 tonnes as the UK average. Helpfully it gives you the ability to drill into where the footprint is heaviest - in my case that’s travel, which I have to do a lot of for work. The good news here is that Farfetch are serious about being more sustainable as a business1 so I’ll be picking this up at work to check whether my travel is currently being offset and if not, why not. Recalculating using my own travel and excluding work results in 16.5 tonnes (157% of target). Drilling down I can still see that carbon footprint is still mostly down to travel (45%). There’s also a good chunk (18%) in the stuff’ category which is caused by all the purchases we’ve made because of our recent house move.

Overall, this is a really helpful calculator and it’s very usable. It’d be nice to be able to work out my family’s footprint instead of just mine, but other than that it’s good.

Carbon Footprint calculatorCarbon Footprint calculator

Calculator 2: Carbon Footprint - https://www.carbonfootprint.com/calculator.aspx

This calculator does allow you to work out your family footprint and even though the UI for the calculator is a little bit rudimentary, it does the trick. You’ll need to have a fair amount of data at hand (or be prepared to take well-informed guesses) to complete it though.

Results on this calculator showed that my family footprint was 16.85 tonnes. They say that the average UK footprint is 6.5 tonnes so we’re way over that.

Carbon Independent calculator FBCarbon Independent calculator FB

Calculator 3: Carbon Independent - https://www.carbonindependent.org

The data for this calculator was updated in 2019 which is encouraging and again allows you to work out a family footprint. I really liked this calculator as it used informed default figures and allowed you to work from these if you didn’t have access to your own data. It also used simple language in the form and showed the immediate affect of your answer as tonnes. For example, when asking about your food miles you’re given good old fashioned radio buttons with labels of very little’, average’, above average’ and almost all’ and as soon as you select you see the amount of tonnes of CO2 that causes.

According to this site the UK average is 14.1 tonnes and our result on this site was 15.34 tonnes.

United Nations Carbon Offset Platform calculatorUnited Nations Carbon Offset Platform calculator

Calculator 4: United Nations Carbon Offset Platform - https://offset.climateneutralnow.org/footprintcalc

Another household calculator and this one’s pretty easy to use too. It’s nice to look at and you can see that there’s been care shown in the look and feel. The calculator breaks into 3 sections; household, transport, and lifestyle and you can get to an answer pretty quickly.

The breakdown on this calculator suggested that 65% of my footprint was caused by a knife and fork symbol - the rest going on symbols for a lightning strike, a car and a plane. I’m not sure how these link to the 3 sections in the calculator, but I suppose it’s saying my lifestyle is the biggest driver here. Going back into the calculator the questions here are about diet, local and responsible consumption and how we handle waste.

Result: 23.53 tonnes against a UK average of 32.49 tonnes.


Mostly, I’m pretty confused still about what our carbon footprint is, as the figures are pretty inconsistent. I don’t know if we’re a particularly good or bad producer of CO2 in comparison to the rest of the UK (however as I live in Europe I can say I know we’re bad when compared to the rest of the planet). What I have taken away from the calculators is that I should do something about the work travel and that we can be better on the food side of things.

In terms of a figure for the carbon offsets, I’m going to use the UK average figure from the UN which would more than cover the calculated impact from 2 of the other calculators and equals the personal impact of the WWF.

  1. Update 2020.01.06 - Farfetch will be offsetting flights.↩︎

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Offsetting our carbon dioxide Note: this is the second part of my notes about how I offset my family’s expected CO2 footprint for 2020. The first part describes how we calculated