Vehiclekilometres

Vehiclekilometres, often written as vehicle kilometres travelled, is a metric that sums the distance driven by all vehicles within a defined area over a specified time period. It is commonly abbreviated as VKT and can be reported for a road network, a city, a region, or an entire country. Some datasets use the single term vehiclekilometres, while others employ vehicle-kilometres or vehicle kilometres travelled.

Measurement and data sources: VKT is typically estimated by aggregating individual vehicle distances from traffic counts, GPS traces, odometer readings, or travel surveys. It can be reported as a total for a region in a given year, or as an average per vehicle, per day, or per route. VKT is distinct from metrics such as passenger-kilometres or tonne-kilometres, which weight distance by passengers or goods carried.

Applications: The metric is widely used in transport planning and policy analysis. It informs infrastructure design, road capacity planning, congestion management, and traffic forecasting. VKT is also a key input to fuel consumption models and greenhouse gas emission estimates, since emissions generally increase with distance travelled and depend on traffic mix and speed.

Limitations and considerations: VKT does not capture trip purposes, travel time, or congestion intensity directly. Data quality and collection methods vary, which can affect comparability across regions or years. Privacy concerns may arise with GPS-based data. When used, VKT is often interpreted alongside other indicators to provide a fuller picture of mobility and environmental impact.