For a large percentage of the car-buying public, the physical dimensions of a vehicle are far less important than some of its other aspects. For instance, considerations like the purchase price of a vehicle, its annual running costs, its warranty period, and warranty conditions or insurance costs often take precedence over any other considerations.
Nonetheless, there are times when a vehicle’s actual size may be an essential factor in a buying decision, especially when a vehicle is purchased for a specific purpose, such as carrying a particular type of cargo. In these cases, factors like the available interior volume, seating arrangement, and the ease of access to parking spots may be more important than the vehicle's annual running costs or its true cost of ownership in terms of insurance and maintenance costs.
Therefore, to help you make an informed decision on which vehicle, or class of vehicle, might best suit your needs, we have compiled some comparative data on vehicle dimensions you might find useful and/or informative. Let’s get started!
How Vehicles Are Classified In The U.S. Market - Find the best car deals!
Unlike most other markets that use a single scheme to classify vehicles, there are currently four different federal agencies in the US that classify vehicles for various purposes. Limited space precludes a comprehensive discussion of these different purposes. Still, we can do the next best thing, highlighting the main differences in how two of these agencies classify vehicles. In practice, these classification criteria are derived from the 13-rule set used by the FHWA (Federal Highway Administration), which forms the basis of how each state classifies vehicles for regulatory purposes.
There is a considerable amount of overlap and ambiguity in vehicle classification schemes across the 50 States. For instance, a vehicle that is classified as a sub-compact in one jurisdiction based on its length, weight, height, and width may qualify as a compact vehicle in another jurisdiction that uses the vehicle’s interior volume as the principal classification criterion. Thus, as a result of these ambiguities, it is challenging to provide average dimensions* of light vehicles that apply to all vehicle categories in all jurisdictions.
*Refer to the table at the end of this article for some comparable data on the average lengths of some vehicle categories available in the US market.
EPA (Environmental Protection Agency) Classification Rules - Find the best car deals!
This scheme’s official title is “Title 40—Protection of Environment, Section 600.315-08 "Classes of comparable automobiles,” and it uses the interior volume index of passenger vehicles, which is defined as the combined cargo and passenger volume of a vehicle. Details are in the table below:
| Vehicle Size Classes by U.S. Fuel Economy Guide for Sedans |
| Vehicle class | Interior Volume Index |
| Mini compact | 85 cubic feet |
| Subcompact | 85 to 99.9 cubic feet |
| Compact | 100 to 109.9 cubic feet |
| Mid-size | 110–119.9 cubic feet |
| Large | >120 cubic feet |
Note that the EPA classifies station wagons as a separate vehicle category. Details are in the table below:
| Vehicle Size Classes by U.S. Fuel Economy Guide for Sedans |
| Vehicle class | Interior Volume index |
| Small | 130 cubic feet |
| Mid-size | 130 to 159 cubic feet |
| Large | >160 cubic feet |
Instead of interior volume indexes, the EPA uses a metric known as the gross vehicle weight rating (GVWR) to classify light trucks, further defined as Non-passenger Vehicles. However, the non-passenger class also includes small pickup trucks, standard pickup trucks, vans, minivans, and SUVs for reasons that are not entirely clear. Note that in 2013, the EPS began to subdivide the SUV category into small SUVs and standard SUVs. At this time, the EPA also introduced a distinction between trucks and SUVs based on each vehicle’s gross vehicle weight rating, with a maximum allowable GVWR of 8,500 pounds for both trucks and SUVs. Consider the table below:
| Vehicle Size Classes by U.S. Fuel Economy Guide for Trucks |
| Vehicle Class | Gross Vehicle Weight Rating |
| Pickup trucks | Small | < 6 000 pounds |
| Standard | 6 000 to 8 500 pounds |
| Vans | Passenger | < 10 000 pounds |
| Cargo | < 8 500 pounds |
| Minivans | < 8 500 pounds |
| SUVs | Small | < 6 000 pounds |
| Standard | 6 000 to 10 000 pounds |
| Special Purpose Vehicles | < 8,500 pounds |
Note that for regulatory purposes, Special Purpose Vehicles are defined as vehicles (including all passenger vehicles) with a GVWR of up to 8,500 pounds fitted with special features and/or devices that, according to the Administrator (of the EPA), are not found on typical vehicles.
NHTSA (National Highway Traffic Safety Administration) Classification Rules - Find the best car deals!
Unlike interior volume indexes, which do not necessarily correlate to any given vehicle’s actual dimensions, the NHTSA uses vehicles’ actual weights to determine classifications to assign NCAP (New Car Assessment Program) safety ratings. Consider the table below:
| NHTSA Passenger Vehicle Classifications by Weight |
| Vehicle Class | Weight Range |
| Passenger cars (Mini) | 1 500 to 1 999 pounds |
| Passenger cars ( Light) | 2 000 to 2 499 pounds |
| Passenger cars (Compact) | 2 500 to 2 999 pounds |
| Passenger cars (Medium) | 3 000 to 3 499 pounds |
| Passenger cars (Heavy) | < 3 500 pounds |
For regulatory purposes, the NHTSA treats pickup trucks, vans, minivans, and SUVs as a single category, but more specifically, as vehicles that are heavier than 3 500 pounds.
As stated elsewhere, it is challenging to provide average dimensions for all US market vehicles. The table below should give some insight into the average lengths of currently available vehicles in various categories. For more detailed information, visit this resource, which provides exact dimensions for each vehicle that can be purchased in the European market today, many of which are also available in the US market. Note that the measurements given below are taken from this resource since similarly curated data is not available for the US market specifically, but be aware that vehicle classifications in the two markets may differ in terms of size classes:
| Average Vehicle Lengths by Category |
| Vehicle Category | Model Example | Vehicle Length in Feet |
| Mini Car/Sub-compact | Suzuki Alto | 10.5 |
| Small Car/ Compact | Kia Rio | 13.8 |
| Mid-sized | Audi A4 | 14.8 |
| Full-sized /Large | Audi A6 | 15.7 |
| Small SUV | Ford Escape | 14.4 |
| Large SUV | Cadillac Escalade | 16.7 |
| Small pickup truck | Nissan Frontier | 16.3 |
| Large pickup truck | Chevrolet Silverado | 18.4 |
Based on the information above, it should be evident that in the US domestic market, there is no single set of rules from which average vehicle dimensions could be extracted. Still, there are ways to get around the confusion if you are looking to replace your vehicle.
One sure way is to obtain the information you need is to compile a short-list of candidate vehicles and then to contact the dealership network for each candidate vehicle to get exact dimensions for each vehicle. Another way is to research each vehicle online, but since not all resources list dimensions beyond the vehicle’s weight, following this route can sometimes be a frustrating and time-consuming endeavor.
Note also that the relationship between a vehicle's weight and its overall dimensions changes all the time. For instance, while American-made vehicles showed sharp reductions in size and weight from about 1973 to the late 1980s, American-made cars have again been getting progressively bigger and heavier. This results from a desire to accommodate features and special safety-related equipment and/or systems that were neither available nor legally mandated until as recently as fifteen years ago.
This trend is likely to continue. Although American cars will likely not reach the 20-foot mark as they did in the 1950s and 1960s, modern vehicles are nevertheless getting bigger, heavier, longer, and wider. It’s something to keep in mind when you compare seemingly identical vehicle models of the same brand.
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