---
title: "Flight carbon calculator — CO₂ per passenger for any flight · Orbit"
description: "Estimate the carbon footprint of a flight between any two of 8,801 airports: CO₂e per passenger, one way or return, with the method shown. London to New York and back is about 1.57 t. Free, no sign-up."
url: https://orbitflights.app/tools/flight-carbon-calculator
---

[Free tools](https://orbitflights.app/tools)

# Flight carbon calculator: how much CO₂ is your flight?

Pick two airports and get an estimate of the emissions per passenger, one way or return, with the method and every factor shown — because the same flight can come out three times higher on one calculator than another.

**Great circle**
5,540 km
3,442 mi each way

**Factor used**
Long-haul
economy · DESNZ 2026

[See this route on the globe →](https://orbitflights.app/distance?from=LHR&to=JFK) [London – New York write-up →](https://orbitflights.app/routes/lhr-to-jfk)

Estimate · per passenger, return

≈ 1.57 t CO₂e

Includes non-CO₂ warming (×1.7) and producing the fuel. 785 kg each way.

CO₂ only, as ICAO counts it: ≈ 756 kg [Why the two differ](#method)

To put that in context

- 33% of the average person's CO₂ for a whole year (4.7 t)
- 63% of a 1.5 °C-compatible yearly footprint (2.5 t)
- 7,480 km driven alone in an average car, for the same emissions

An average for the distance, not a measurement of your flight. The aircraft, how full it is and the route flown all move the real number.

## The footprint of some familiar flights

Per economy passenger, on the method below.

| Flight                  | Distance  | One way | Return |
| ----------------------- | --------- | ------- | ------ |
| London to Paris         | 348 km    | 52 kg   | 103 kg |
| London to Barcelona     | 1,148 km  | 170 kg  | 340 kg |
| New York to Los Angeles | 3,974 km  | 563 kg  | 1.13 t |
| London to Dubai         | 5,498 km  | 779 kg  | 1.56 t |
| London to New York      | 5,540 km  | 785 kg  | 1.57 t |
| London to Singapore     | 10,883 km | 1.54 t  | 3.08 t |
| Sydney to Los Angeles   | 12,061 km | 1.71 t  | 3.42 t |
| Paris to Tokyo          | 9,708 km  | 1.38 t  | 2.75 t |

Methodology

## How the estimate is worked out

**1\. Distance.** The great-circle distance between the two airports — the shortest path over the Earth, the same figure as the [flight distance calculator](https://orbitflights.app/distance). Planes fly a little further than this; the factors below already allow 8% for it.

**2\. Factor.** Flights under 3,700 km use the UK government’s short-haul economy factor, longer ones the long-haul factor. DESNZ draws that line by region rather than distance; the 3,700 km cut-off is our approximation of it for flights anywhere in the world.

**3\. What’s counted.** The CO₂ from burning the fuel, multiplied by 1.7 for non-CO₂ warming (contrails and nitrogen oxides at altitude), plus the emissions from extracting, refining and moving the fuel. Per economy seat, averaged over typical load factors.

**4\. Return trips** are two one-way legs.

__Emission factors used, kg CO₂e per passenger-kilometre__
| Per passenger-km            | Short-haul | Long-haul |
| --------------------------- | ---------- | --------- |
| Flight, with non-CO₂ (×1.7) | 0.12576    | 0.11704   |
| Fuel production             | 0.02249    | 0.02461   |
| CO₂ only (ICAO basis)       | 0.07344    | 0.06826   |
| Headline total              | 148 g      | 142 g     |

kg CO₂e per passenger-km, economy, DESNZ 2026.

### Why calculators disagree

Almost all of the spread is in what gets counted, not in the physics. The [ICAO calculator](https://www.icao.int/environmental-protection/environmental-tools/icec) reports only the CO₂ from burned fuel. Google Flights, through its open [Travel Impact Model](https://github.com/google/travel-impact-model), adds the emissions from producing the fuel. The UK government multiplies the CO₂ by 1.7 for non-CO₂ effects; myclimate and atmosfair multiply by 3\. For London to New York and back, that is the difference between about 756 kg and well over two tonnes.

Non-CO₂ effects are real — the best current estimate, [Lee et al. (2021)](https://www.sciencedirect.com/science/article/pii/S1352231020305689), puts them at about two-thirds of aviation’s warming — but far less certain than CO₂’s. Leaving them out understates a flight; multiplying by 3 is at the top of the range. This calculator takes the UK government’s middle course and shows the CO₂-only number beside it, so you can compare with whichever calculator you saw last.

### The comparisons

- **The average person’s year** is 4.73 t of CO₂ (world, 2024, [Global Carbon Budget](https://ourworldindata.org/grapher/co-emissions-per-capita)). That figure leaves out international flights, so it is a yardstick, not a like-for-like total.
- **A 1.5 °C-compatible year** is 2.5 t CO₂e per person by 2030 ([Hot or Cool Institute](https://hotorcool.org/projects/1-5-degree-lifestyles/)).
- **The car** is the UK average car, tailpipe plus fuel production — 210 g CO₂e per km, one person in it.
- **The train** is UK national rail at 40 g CO₂e per passenger-km over the same distance, shown only when both airports are on the same continent and under 1,500 km apart. Many European high-speed lines run lower than this.

Factors from [UK Government GHG Conversion Factors 2026 (DESNZ)](https://www.gov.uk/government/publications/greenhouse-gas-reporting-conversion-factors-2026) and its [methodology paper](https://assets.publishing.service.gov.uk/media/6a2940543b15d05a7ce3202e/2026-GHG-conversion-factors-methodology-report.pdf). Cabin class and passenger count aren’t modelled here: every figure is one economy seat.

Flight emissions

## Questions about the carbon footprint of flying

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It depends mostly on distance. On this calculator's method, an economy seat costs about 148 g CO₂e per kilometre on short-haul and 142 g on long-haul, including non-CO₂ warming and fuel production. London to New York one way comes to roughly 785 kg.

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## Know the distance behind every flight you’ve taken.

Orbit logs your flights and adds them up — distance, hours, countries and continents — on a globe you can spin. Offline, free to start.

[Download now](https://play.google.com/store/apps/details?id=com.qwertybit.orbit)

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Markdown copy of https://orbitflights.app/tools/flight-carbon-calculator for language models and agents. Site index: https://orbitflights.app/llms.txt