Car emissions calculator

Car emissions calculator

Use the calculator below to compare the emissions for two vehicles. Select vehicles using the drop-down lists, then enter data type (real-word or official figures), mileage and driving style and your results will appear.

Based on your selections, the results will show estimates for total carbon dioxide (CO2), nitrogen oxides (Nox) and particulate (PM10). This is then broken down into direct emissions from the tailpipe at point-of-use, and indirect emissions generated during fuel and vehicle production. See below for full details on the assumptions used in these calculations.

1 Select cars to compare
Select car 1
- cc (0 litre) -
Used car
CO2: g/km NOx/PMs: 0/0 mg/km Euro Standard: Official MPG (Comb): MPG Real MPG (Comb): N/A MPG
Select car 2
- cc (0 litre) -
Used car
CO2: g/km NOx/PMs: 0/0 mg/km Euro Standard: Official MPG (Comb): MPG Real MPG (Comb): N/A MPG
2 Enter data type, mileage and driving style
  • miles

Ready to calculate?

How we calculate CO2, NOx and PM emissions

The Next Green Car emissions calculator estimates total emissions of carbon dioxide (CO2), nitrogen oxides (NOx) and particulate (PM10). The calculator also provides a breakdown of total emissions according to direct (tailpipe emissions at point-of-use) and indirect emissions (emissions generated during fuel and vehicle production).

For all vehicles types, direct tailpipe emissions are calculated by multiplying the official or real-world emissions figure (in grams per km) by the journey distance or mileage (in miles), and a factor representing driving style (‘Normal, ‘ Aggressive/Fast’, ‘Eco-driving’).

Indirect fuel production emissions are based on published data quoted on an energy delivered basis (in grams per giga joule). These values are then multiplied by the vehicle’s official or real-world fuel economy (in litres or kWh per 100 km), the journey distance or mileage (in miles), and a factor representing driving style (‘Normal, ‘ Aggressive/Fast’, ‘Eco-driving’).

Indirect vehicle production emissions are estimated which represent the NOx, PMs, and CO2 emissions associated with the vehicle’s manufacture. The approach is based on a per kg emissions for each vehicle type (petrol, diesel, electric, etc) which is then multiplied by the mass of the model selected.

Confidence levels: Due to the strong correlation between fuel use and CO2 emissions, the estimates for CO2 emissions have a high level of confidence. In contrast, given the high dependency of NOx emissions on driving style and road conditions, the estimates for NOx and PM emissions have a low to moderate level of confidence,

For more details of the methodology used to calculate emissions, download the PDF document: NGC Emissions Calculator Methodology 2016

vehicle emissions calculator
Chris Lilly

Author:Chris Lilly
Date Updated:17th Aug 2017

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