The list was compiled in association with What Car? magazine and is part of the DfT’s Act On CO2 campaign to help tackle climate change.
The list can be seen at www.dft.gov.uk/ActOnCO2.
Jim Fitzpatrick, transport minister, said: "Climate change affects everyone and everyone can make a contribution to tackling it. By choosing the car with the most fuel efficient engine in its class, drivers could reduce their engine CO2 emissions by 24% and potentially save a quarter on fuel costs. So the message is simple - the car you choose can help reduce your impact on the environment, and help save money."
The Best on CO2 rankings were developed using emissions data from the Vehicle Certification Agency, the DfT agency responsible for conducting the official tests to determine CO2 emissions from cars.
The Society of Motor Manufacturers and Traders welcomed the new initiative.
Christopher Macgowan, SMMT chief executive, said: “Consumers need to make the connection between choosing the most CO2 efficient cars and lower cost motoring.
“They also need to be clear on the practical steps to be taken to limit their carbon footprint in action, whatever vehicle they drive.”