AIR Index EXCLUSIVE: First comprehensive Euro 5 and Euro 6 data set of on-road emissions for NOx and CO2.

The missing link between actual on-road emissions and official Euro ratings. Look-up the AIR Index rating now.

The AIR Index

The AIR Index helps consumers, fleet managers and policy makers make informed decisions based on independent, on-road emission tests.

The AIR Index is an independent vehicle emissions rating for cars and vans. Ratings range from A (the best) to E (the worst), based on the actual on-road urban NOx and CO2 emissions using the same independent test on every single vehicle.


An independently tested and verified
measure of how much CO2 is released
by each vehicle.

Urban NOx

An independent real-life measure of
harmful NOx emissions contributing
to poor air quality.

Low Emission Petrol Cars

Find the lowest emission petrol cars on the market or find ratings for older vehicles.

Low Emission Diesel Cars

Choose the right diesel for you and compare vehicles with real-life emissions data.

Low Emission Vans

Find the lowest emission vans and light-duty vehicles from our on-road emissions tests.

Low Emission SUVs

See the independently tested list of the lowest emission SUVs on the market.

Fleet Managers

How the AIR Index can help fleet managers reduce the total cost of ownership (TCO) by choosing the cleanest vehicles to deliver long-term benefits.

Policy Makers

How policy makers can improve air quality in towns and cities with the AIR Index; a more realistic and accurate measure of NOx emissions than Euro ratings.

Vehicles Tested with the AIR Index

Confidence through transparency

The AIR Index has been led by a global alliance of scientists and organisations. We are committed to reducing harmful vehicle emissions by providing car and van buyers and policy makers with a trusted and independent way to evaluate each model.

While not every variant of every model can be tested, there is a programme underway to evaluate as wide a range of vehicles as possible according to the CWA17379 methodology.

We also include predicted ratings for models which have not yet completed testing in full compliance with CWA17379. These are displayed in the search results with the relevant AIR Index rating ‘blanked out’ as they are not full AIR Index ratings. The predicted rating does provide an indication of the expected result for the on-road urban NOx and CO2 emissions when it is tested in accordance with the CWA17379 European protocol.

The CEN Workshop Agreement CWA17379 was initiated by Nick Molden of Emissions Analytics, which has tested more than 2,000 vehicles, including over 1,000 in Europe since 2011. Together with test data from several other organisations and companies, independent from car makers, the AIR Index has been created reflecting this extensive experience.

Request a vehicle test

If there is a vehicle you would like to see tested, please let us know by sending an email to for us to consider.

The AIR Index Method

Each car and van is independently tested in accordance with a voluntary standardised European protocol CWA17379.

This approach allowed the practical experience gained from years of commercial on-road testing by Emissions Analytics to be combined with expertise from a wide range of leaders in emissions control, emissions policy and air quality.

The resulting standardised method can be used by any test centre to collect comparative emissions data, which can then be fed into the AIR Index ratings system.

Every AIR Index rating requires at least two vehicles of the same type to be tested at least three times, recording at least five x 10km trips, which each take approximately 20 minutes and in full compliance with the boundary conditions specified in the protocol.