WLTP stands for Worldwide Harmonized Light-Duty Vehicles Test Procedure. This worldwide harmonized testing procedure for light-duty vehicles describes a new testing method to determine a vehicle’s fuel consumption. This procedure is based on real recorded driving data and helps to simulate realistic driving even under laboratory conditions. That is why WLTP not only takes into consideration various situations and speeds but also a vehicle’s different equipment variants and weight classes. 

A vehicle's actual consumption may differ from the information provided by the manufacturer. That is why the reliability of the results measured using the New European Driving Cycle (NEDC) has always been criticized. This is due to the fact that real consumption is highly dependent on individual driving behavior and the vehicle’s equipment. One example is whether a vehicle is primarily used in the inner city, on rural roads or the highway. To address these differences, the theoretical framework of the NEDC has been revised to reflect a more dynamic driving profile. Drawing on statistical surveys and the analysis of average user profiles, this profile features higher acceleration, a higher average speed and a higher maximum speed. Instead of combining simulated urban and extra-urban driving, the vehicle is now tested in four phases and speed ranges. 

The exhaust and consumption values measured as per WLTP must be specified for all new passenger vehicle models launched as of 1 September 2017. This applies in Europe and many other countries worldwide.