Automakers include a lot of measurements when they’re telling you about a vehicle. From horsepower and trunk volume to headroom, ground clearance, and infotainment screen sizes, there are many dimensions that they think car buyers should know. To be fair, much of the information they provide is useful. I certainly appreciate knowing the EPA-estimated fuel economy of my vehicle, and whether there is enough legroom for my six-foot-one frame to fit comfortably.
However, there are many measurements I’d like to know that are next to impossible to find. Furthermore, some of the information automakers provide isn’t clear or specific enough to have practical applications. A quick internet search shows I’m not alone, with discussions lamenting everything from rearview mirror size to the cupholders, laments that could have been avoided if the info was readily available before purchasing.
I believe there is a disconnect between what measurements manufacturers think are important and what matters for modern consumers. With that in mind, here are six measurements I think should be provided or made clearer to help people choose their next vehicle.
Cupholder Size (Standard vs Non-Standard)
A cupholder is a cupholder, right? Not when it comes to vehicles. One of the most revealing findings of the 2025 J.D. Power U.S. Initial Quality Survey is that car owners are increasingly frustrated with cupholders, impacting what they buy. Unfortunately, while many automakers list the total number of cupholders, few provide the size, leaving consumers to find out for themselves.
Granted, people now use a variety of cups, bottles, and containers. They sometimes put food, keys, coins, and even phones in the cupholders. But that makes knowing the cupholder dimensions even more important. Is the cupholder a standard or non-standard size? Does it get narrower at the bottom? Will a travel mug with a handle actually fit in the cupholder? Curious minds need an answer, as they don’t want to buy a car and then discover the cupholder isn’t big enough to hold their favorite travel mug.
Phone Holder Size
Whether they come with the car or are added as an aftermarket accessory, phone holders are nearly as ubiquitous as cup holders. They’re much needed to control your playlist or see Google Maps while maintaining at least some road vision. However, it can be incredibly hard to find out in advance what phones fit, since manufacturers rarely mention the holder size.
Although a diagonal screen of 5.5 to 6 inches is the most common size range, many smartphone sizes are out there, and new models are introduced seemingly daily. No one wants a mount that can’t hold their phone, but apart from a few exceptions, the only way to know for sure is to try to put a phone in the holder. I’d much prefer to know ahead of time if a holder is the right size rather than be surprised by it.
Rearview and Sideview Mirrors
Visibility is a must in a vehicle, not just what’s ahead, but what’s beside and behind you. Yet when was the last time an automaker or dealership told you how big the rear and side mirrors are? The larger the mirrors, the more you’ll be able to see. But while you’ll hear plenty about features like auto-dimming, integrated tech, and heaters, good luck getting a straight answer about the sizes of the mirrors.
I’ve found that the typical rearview mirror size is around 10 inches wide and three inches tall, and sideview mirrors tend to be around nine inches wide. Those are far from universal sizes. For example, rearview mirrors can be as wide as 12 inches or as narrow as nine inches. You also don’t hear much about whether the mirrors are panoramic, convex, or any other form that might affect vision.
Middle Seat Size
Whether in the second row, third row, or both, bench seats remain common to maximize the number of passengers in a vehicle. But until people sit on those benches, they don’t know whether the middle seat is going to be comfortable. I have yet to find an automaker that lists the size of the center seat, which creates a mystery that I’d much rather be solved from the start.
Typically, automakers will tell you the rear hip room and shoulder room, but from what I can tell, this is just based on the total bench seat length and vehicle width. When you see that a Toyota Camry has 54.6 inches of rear hip room, you can’t tell whether that’s evenly distributed across all seats, or if you have giant 20-inch end seats and a tiny 14.6-inch middle seat. Inquiring minds want to know if an adult can fit comfortably in the middle seat, or if the youngest kid will always get stuck squeezing in there.
Stopping Distance
Automakers provide plenty of information about the braking system. Choosing the Ford Mustang specs to illustrate, you can learn the brake rotor size, how many pistons the calipers have, whether the brakes are vented, whether electronic assistance is included, and even the brake rotor brand. There’s one notable measurement missing, though. What stopping distance does all this translate to? I would argue that’s the most important info to have, as ultimately, this determines whether you can slow down in time to make a turn or avoid a crash.
There are guides online with general stopping distances for different speeds, but they don’t consider the vehicle size or whether the vehicle has a performance braking system. Right now, the only way to find a specific vehicle’s braking distance is from independent testing organizations like Consumer Reports. To be fair, there are several variables, including road conditions, tire conditions, and cargo load. Still, it would be great to know how much room you have to work before you slam the brakes for the first time.
Cargo Capacity
This might seem an odd inclusion, as cargo volume is a universal measurement on basically every spec sheet. My beef, though, is threefold. First, a volume measurement doesn’t explain what I can do with that space. If a vehicle is advertised as having 40 cu.ft. of storage, what does that mean? Can the trunk hold four suitcases? Twelve? Will it hold a PA amplifier or a small bookshelf?
Second, I always receive the cargo volume, but rarely the other dimensions (except with truck beds). Forty cu.ft. can be achieved with many height, length, and width combinations, which changes what fits in the space. Finally, I’ve found that with SUVs and hatchbacks, many automakers focus on promoting maximum storage space with all but the front row of seats down. While this has its uses, it’s not how most people travel. After all, 100 cu.ft. of cargo space with the seats down does you no good if the seats are always full of passengers.
The Measurements People Need to Know
To a point, it’s understandable that automakers keep giving us the same dimensions they always have. Why fix what isn’t broken? Well, I’m here to say there are some cracks. Knowing the measurements of cupholders, rearview mirrors, middle seats, and other items, along with clarifying common design elements, is important to present-day drivers. These factors play a big role in safety and comfort, so people like me don’t want to leave them to chance.
Will manufacturers eventually start giving us some of these measurements? I think that, more than anything, it depends on how much fuss people make. As the saying goes, you give the people what they want. If people make it known they want certain measurements and are making purchases based on those things, it’s only a matter of time before automakers come around.
