To help you make more sustainable travel choices, you can find carbon emission estimates on your flight search results and booking pages.
Find carbon emission estimates
- Go to Google Flights.
- Search for a flight.
- On the right, click the down arrow.
- You'll find the emission estimates for each part of your trip.
Sort by carbon emissions
- On the right, click Sort by CO2 emissions.
- Your flight search results will be ordered from lower to higher emissions.
How we estimate carbon emissions
Google uses the European Environmental Agency (EEA) emission estimates with the most up-to-date algorithmic model from 2019. Learn about the model with the EEA guidebook.
Why some flights have lower emissions
Carbon emission estimates consider the origin, destination, aircraft type, and the number of seats in each seating class.
Factors such as fuel-efficient aircraft and shorter routes usually result in lower carbon emissions.
The emission estimates are higher for premium economy, business, and first seating classes because the seats in these sections take up more space. They'll account for a larger share of the flight's total emissions.
Traveling by train
When a train is available on your route, you'll find it listed on your Google Flights search results.
Traveling by train may result in significantly lower carbon emissions compared to flying. Carbon emissions for trains are compared to the typical flight for that route. As such, train options are mostly marked with a badge indicating lower emissions.