Q: What is the difference between CO2 and CO2e in flight emissions?

CO 2 refers only to the carbon dioxide released by burning jet fuel. CO 2 e (CO 2 -equivalent) is a broader measure that also accounts for other warming effects — such as contrails, nitrogen oxides, and water vapour released at cruise altitude. Because these non-CO 2 effects roughly add 70% on top of the direct combustion CO 2 , the true climate impact of a flight is approximately 1.7x the fuel-burn CO 2 alone. Our calculator reports the full CO 2 e figure so you see the complete picture.

Q: Where does the emissions data come from?

We source emissions data from two places. The Google Travel Impact Model provides per-passenger CO 2 figures based on aircraft type, fuel efficiency, load factors, seat configuration, and route distance. For flight-number lookups, we also use the Aero Data Box API to resolve your flight to a specific aircraft and route. Our non-CO 2 multiplier is based on peer-reviewed research by Lee et al. (2021) and is aligned with UK DEFRA’s latest greenhouse gas reporting recommendations. See our full calculation methodology for details.

Q: What does "Well-to-Wake" mean?

It’s the full lifecycle of aviation fuel. Tank-to-Wake (TTW) covers the CO 2 released directly during your flight from burning fuel. Well-to-Tank (WTT) covers the CO 2 produced upstream — extracting crude oil, refining it into jet fuel, and transporting it to the airport. Together, Well-to-Wake (WTW) gives you the complete CO 2 footprint of the fuel your flight uses.

Question 1

How does a flight carbon calculator work?

Accepted Answer

Our flight carbon calculator estimates the total climate impact of your flight — not just the CO₂ from burning jet fuel, but also the upstream emissions from producing that fuel and the non-CO₂ warming effects of flying at high altitude. We use the Google Travel Impact Model, which factors in aircraft type, fuel efficiency, passenger load, seat configuration, cabin class, and route distance to give you a per-passenger emissions figure in kilograms of CO₂e. Learn more about our methodology.

Question 2

How do I calculate the carbon footprint of a flight?

Accepted Answer

You can use the calculator in two ways. For the most accurate result, enter your flight number and departure date — we’ll look up the exact aircraft, airline efficiency data, and route. Alternatively, you can enter your origin airport, destination airport, year of travel, and cabin class for a reliable route-based estimate.

Question 3

Why does the calculator ask for my cabin class?

Accepted Answer

Cabin class has a significant effect on your per-passenger emissions. Business and first class seats take up more physical space on the aircraft, which means each passenger in those cabins is allocated a larger share of the plane’s total fuel burn. Economy class passengers share the fuel cost across more seats, resulting in lower per-person emissions.

Question 4

How accurate is your flight carbon footprint calculator?

Accepted Answer

Our calculator uses the Google Travel Impact Model (TIM), which is the same model used across the travel industry. When you provide a flight number and date, we retrieve flight-specific data — including the exact aircraft type and airline — for the highest possible accuracy. Even with just a route and cabin class, the model uses robust industry averages for load factors (how full the flight tends to be), aircraft mix, and fuel efficiency on that route.

Question 5

How much CO2 does a flight produce per passenger?

Accepted Answer

It varies significantly depending on the route, aircraft, airline, and cabin class. A short-haul economy flight might produce 50–150 kg of CO₂e per passenger, while a long-haul business class flight can exceed 1,000 kg CO₂e. Our calculator gives you a specific figure for your exact route and travel details rather than relying on rough averages.

Question 6

What is the difference between CO2 and CO2e in flight emissions?

Accepted Answer

CO₂ refers only to the carbon dioxide released by burning jet fuel. CO₂e (CO₂-equivalent) is a broader measure that also accounts for other warming effects — such as contrails, nitrogen oxides, and water vapour released at cruise altitude. Because these non-CO₂ effects roughly add 70% on top of the direct combustion CO₂, the true climate impact of a flight is approximately 1.7x the fuel-burn CO₂ alone. Our calculator reports the full CO₂e figure so you see the complete picture.

Question 7

Where does the emissions data come from?

Accepted Answer

We source emissions data from two places. The Google Travel Impact Model provides per-passenger CO₂ figures based on aircraft type, fuel efficiency, load factors, seat configuration, and route distance. For flight-number lookups, we also use the Aero Data Box API to resolve your flight to a specific aircraft and route. Our non-CO₂ multiplier is based on peer-reviewed research by Lee et al. (2021) and is aligned with UK DEFRA’s latest greenhouse gas reporting recommendations. See our full calculation methodology for details.

Question 8

What are non-CO2 effects and why do they matter?

Accepted Answer

When aircraft fly at high altitude, they produce climate-warming effects beyond just CO₂. These include contrails (the white trails that trap heat), nitrogen oxides (which affect ozone and methane levels), and water vapour released where it has a stronger warming effect. Scientific research shows these non-CO₂ effects can add around 70% to the direct combustion CO₂ impact, making the total climate footprint of flying roughly 1.7 times the CO₂ alone.

Question 9

What does "Well-to-Wake" mean?

Accepted Answer

It’s the full lifecycle of aviation fuel. Tank-to-Wake (TTW) covers the CO₂ released directly during your flight from burning fuel. Well-to-Tank (WTT) covers the CO₂ produced upstream — extracting crude oil, refining it into jet fuel, and transporting it to the airport. Together, Well-to-Wake (WTW) gives you the complete CO₂ footprint of the fuel your flight uses.

Question 10

How can I put my flight emissions into context?

Accepted Answer

We convert your results into everyday equivalences so the numbers mean something tangible: Days of UK household emissions (~28.5 kg CO₂e/day), Kilometres driven (136 g CO₂/km), Weeks of household electricity (~40.4 kg CO₂e/week), Kettles boiled (~15 g CO₂ each). For example, a London-to-New York return flight in economy might equate to roughly 30+ days of average UK household emissions.

Question 11

Why are my flight emissions higher than other calculators show?

Accepted Answer

Many flight carbon calculators only report direct CO₂ from fuel burn. Our calculator includes the full climate impact: direct CO₂, upstream fuel emissions, and the non-CO₂ warming effects (contrails, NOx, water vapour). This gives a more complete and scientifically honest picture of flying’s climate impact. We believe it’s better to understand the true footprint so you can take meaningful action. You can read exactly how we calculate these figures.

Question 12

How much carbon emissions come from flying?

Accepted Answer

Aviation accounts for roughly 2–3% of global CO₂ emissions from fossil fuels. However, when you include non-CO₂ warming effects — contrails, nitrogen oxides, and water vapour released at high altitude — flying’s total contribution to climate change is estimated to be around 3.5–4% of human-caused warming. While that might sound small, it’s concentrated among a relatively small share of the global population — only around 10–20% of people fly in any given year.

Question 13

Can I offset my flight's carbon footprint?

Accepted Answer

You can fund verified climate projects to take responsibility for your flight emissions. We deliberately avoid calling this “offsetting” because it implies your emissions are cancelled out — they aren’t. Instead, think of it as funding climate action: supporting projects that avoid or remove emissions elsewhere. After calculating your flight’s impact, you can fund an equivalent amount of verified carbon projects directly through our platform.

Question 14

What can I do about my flight emissions?

Accepted Answer

Flying connects families across continents, opens up new cultures, and keeps the global economy moving. But it’s also one of the more carbon-intensive things most of us do, and it’s worth taking seriously.

There are some straightforward ways to reduce your impact before you even get to the airport. For shorter journeys, the train is often just as convenient and a fraction of the emissions. When you do fly, choosing a direct route over a stopover makes a real difference because layovers add more take-offs and landings, which is where fuel burn is highest. Flying economy also matters more than people realise: business and first class seats take up significantly more space and carry a larger share of the aircraft’s total emissions.

When flying is the right choice, the most honest thing you can do is know your actual impact and take responsibility for it. Use an accurate calculator like this one to understand the climate cost of your journey, then support verified carbon projects that either avoid emissions or actively remove carbon from the atmosphere.

It’s not a free pass, but it’s a meaningful step, and it funds the kind of climate solutions the world urgently needs more of.

Question 15

Is funding carbon credits for my flights enough?

Accepted Answer

You’ll notice we don’t use the word “offsetting” much here, and that’s deliberate. It’s a term that implies your emissions are cancelled out, neutralised, or erased. They aren’t. No amount of funding climate projects undoes the carbon that went into the atmosphere when your flight took off. “Offsetting” has become shorthand for a transaction that lets you off the hook, and we don’t think that’s an honest framing.

What we’d encourage instead is thinking of it as funding climate action. That means supporting verified projects that avoid or remove emissions elsewhere in the world, alongside your own efforts to reduce the flights you take in the first place.

Does that make it “enough”? Honestly, not on its own. The most meaningful thing any of us can do is reduce emissions at source: fly less, choose the train for shorter trips, pick direct routes. But for the flights that are genuinely worth taking, calculating your climate impact accurately and directing real money towards high-integrity climate projects is a responsible and worthwhile step. It contributes to real-world emissions reductions. It funds solutions the world needs. And it’s far better than doing nothing.

Rather than asking whether it’s enough, think of it as part of a bigger picture: reduce what you can, and take meaningful action on the rest.

Calculate your flight emissions

Frequently asked questions

Calculate your flight emissions

Frequently asked questions