Most flight CO2 calculators use a simple distance-based formula. FLY uses the ICAO fuel-burn methodology: real aircraft-type fuel consumption data (3.15 kg CO2 per kg of jet fuel), actual route distances from 25,600+ IATA data points, and cabin class multipliers that reflect the real floor space each seat class occupies.
Enter a flight number to pull live aircraft type from FlightRadar24, or enter a route directly. FLY breaks down your CO2 by leg for multi-city trips and shows economy, business, and premium economy side by side.
Examples
Example flight CO2 figures
Dublin - London
~82
kg CO2 per passenger
Economy · A320 · 460km
London - New York
~530
kg CO2 per passenger
Economy · 787-9 · 5,540km
London - Dubai
~1,450
kg CO2 per passenger
Business class · A380 · 5,475km
Sydney - Singapore
~670
kg CO2 per passenger
Economy · A330 · 6,300km
Methodology
How FLY calculates CO2
FLY uses a four-factor model based on ICAO guidance. Every factor is pulled from real data, not generic averages.
Factor
Source
Why it matters
Fuel burn rate
Aircraft-specific ICAO profiles, 65+ types
A 787-9 burns 35% less fuel per seat than a 747-400 on the same route
Route distance
25,600+ IATA great-circle distances
Per-km averages miss hub connections and indirect routings
CO2 per kg fuel
ICAO standard: 3.15 kg CO2/kg fuel
Jet fuel has a fixed emissions factor used by all ICAO signatories
Cabin class multiplier
Seat pitch and floor space ratios
Business class seats occupy 2-4x the floor space of economy, earning a proportional CO2 share
Get Started
Calculate your flight CO2 now
Free, no account needed. Takes 30 seconds. Get your precise kg CO2 figure and optionally support verified removal.
A flight CO2 calculator uses route distance, aircraft type, fuel burn rate, and cabin class to estimate CO2 per passenger. FLY uses the ICAO methodology: 3.15 kg CO2 per kg of jet fuel burned, with real aircraft fuel consumption data and cabin class multipliers.
Economy class: 80-120g CO2 per passenger-km on short haul; 90-115g on long haul. Business class adds a 2-3x multiplier, reaching 180-350g per passenger-km. These vary significantly by aircraft type which is why FLY uses per-flight calculations rather than per-km averages.
The most accurate calculators use real aircraft fuel consumption data, ICAO methodology, and cabin class multipliers. FLY cross-references 25,600+ IATA route records, 65+ aircraft type fuel profiles, and live FlightRadar24 data for flight number lookups to give per-flight precision.
A short-haul flight under 3 hours typically produces 80-150 kg CO2 per economy passenger. The exact figure depends on aircraft type, configuration, and load factor. Business class adds a 2-3x multiplier.
Yes. FLY supports multi-city trips with per-leg CO2 breakdown and a total. Enter each leg and see cumulative CO2 for your entire journey.