Carbon Footprint

Features

• Itemised annual emissions for electricity / gas / petrol / diesel / public transport / flights / diet
• ⚠️ Every factor is a named constant with a source and year (IEA, DEFRA/BEIS, Scarborough / Poore & Nemecek)
• Total, per-person figure, and a comparison with the world average and the 2-tonne target
• Names the largest item and its share
• Diet in four bands (meat-heavy / average / vegetarian / vegan), multiplied by household size
• Flights split into short-haul and long-haul, with radiative forcing
• ⚠️ States plainly that it is an estimate and that it does no offset conversion
• Computed locally with no network requests

How to use

1. Enter monthly electricity and natural gas use
2. Enter monthly petrol and diesel use and public transport distance
3. Enter the number of short-haul and long-haul flights per year
4. Pick a diet and the number of people
5. The right-hand side gives each item, the total, per person and the largest source

FAQ

Why can “carbon per kWh” not be a single number?

Because grid carbon intensity depends on the local generation mix. Nuclear-dominated France is about 0.05 kg CO₂/kWh; coal-heavy grids exceed 0.9 — nearly 20 times as much. This tool uses the IEA 2023 world average of about 0.45 and states the source in the result; for a closer fit, substitute your local grid intensity. That is also why every factor here carries a source and year instead of a casual “about 0.5”.

Can I use this for carbon accounting or offsets?

No. It is an order-of-magnitude estimate for judging which item dominates and roughly how far you are from the world average and the 2-tonne target. Carbon accounting needs activity data, emission factors, boundaries and assurance; offsetting is yet another set of books (project certification, additionality, double counting). Turning a rough estimate into “equal to planting N trees” would imply the precision of an inventory — which is why this tool deliberately does not do it.

Which item is usually largest?

For most urban households, travel (especially flights and private cars) and diet are often the two largest; electricity and gas usually trail. A single long-haul return flight is often around a tonne per passenger — comparable to a household’s entire year of electricity. That is why the largest item is singled out here: so “what to change first” has a basis.