Size differences betwee different car classes

In my opinion, there isn’t any. What’s a compact today might have been mid-sized 20 years ago.

Sure we can break out the measuring tape, and get an aggragate of every car’s dimensions. But for me, I let the measurements matter when they need to and base my understanding of car sizes into the following:

City
Sub compact
Compact
Mid-size
Large
Full-size

It’s flexible enough to allow for things smaller than City cars and things larger than Full-size cars, but for now, I stick to the above.

I also pretty much let the automakers dictate what they say their car is and for the last 15 years it’s worked for me. I don’t overlap the segments, IE: the Cruze is not a compact mid-size, it’s just a fat compact – a compact as designed and engineered by GM.

That “fattness” of the Cruze is just an attribute of what GM felt was best for their compact car offering in North America. Arguably, it might not have been the wisest decision for them, but that is what GM calls a compact and it fit with my system.

For me, my system works as I can easily relate one car in a segment with another in the same segment. I don’t include price because (for example) in compact segment, you can spend as much as you want and still have a compact car, be it a Kia Rio or a M3. There are things a compact Rio and M3 can both do, and something that only one can do that the other can’t. The difference does come down to need and desire. Some would say that the Rio is the better car because it does X, Y, and Z better than the M3 and that for their money, that’s what matters.

I’m not saying my system is bullet proof, but that’s how I make sense of car sizes in their respective segments.

It’s the interior volume that is used. Passenger and cargo space. EPA guide lines. Mini compact less than 85 cubic feet. Subcompact 85 to 99. Compact 100 to 109. Midsize 110 to 119. Large 120. So the Cruze, Malibu, Malibu with e assist and regal are midsize. The Verano and regal with e assist are compact. I think they use SAE J1100 to measure the interior volume

@Mainwayne

I wouldn’t trust the EPA to have any idea on how to classify car sizes. Their metric is so left-field, it might as well be applicable to tricycles built for circus animals.

Here is the EPA page with the chart as found in the “How are vehicle size classes defined?” link:
http://www.fueleconomy.gov/feg/info.shtml

Here’s a link to Nissan USA’s page for the 2013 Nissan Versa:
http://www.nissanusa.com/versa-sedan/specifications/

Under “capacities”, you’ll find the Versa has an interior volume of 90.2 cubic feet, which according to the EPA would put the Versa in the Subcompact segment. With me so far?

Now lets try something that nobody would call a subcompact, a Bentley Continental GT!

Since Bentley doesn’t list the interior volume on it’s website, I’ve had to get an average from 3 different sources:

http://www.autobytel.com/bentley/continental-gt/2013/specifications/
^ they say the GT has 89.0 cubic feet.

http://www.cars.com/bentley/continental-gt/2012/specifications/
^ cars.com says 89.0 cubic feet.

http://www.thecarconnection.com/specifications/bentley_continental-gt_2013_2dr-cpe_dimensions
^ TCC says 89 cubic feet.

And guess what? The EPA says that the 6L, twin-turbo, W-12 powered, 5000lb, $190K, 616hp, 590ft-lb 2012 Bentley Continental GT is a Subcompact….just like the Nissan Versa. The EPA, as well intentioned as it is, isn’t catergotizing cars based on their fuel effieciency, the very thing that would put the Versa up the chart and the Continental further down were it would be subject to taxation.

Now you know why the EPA doesn’t have clue on how to size cars properly.

I agree the EPA doesn’t have a clue( what government agency does). Under their guide line the Regal is a midsize Regal with E assist is a compact . It is interesting that the Bentley Contintal GT is a 616 HP subcompact.

@chevtothemax Here are some interesting interior metrics that you can use to see the difference between a midsizer like a Malibu/Regal and a compact (Cruze):
http://gmauthority.com/blog/2012/10/just-how-spacious-is-the-2013-chevy-malibu/

That said, the Regal and Malibu are on the smaller side of the midsize segment… but their larger size is still felt in the dimensions of the vehicle (length and width) as well as the width of the cabin. I expect the next-gen midsizers from GM to add an inch or two to the wheelbase and grow interior volume accordingly, if not more — since space efficiency is paramout nowadays.