Guide to Choosing the Right Size Speakers for Your Car

How to Choose the Right Size Car Speakers

Are you looking to upgrade the stock speakers in your car but aren’t really sure where to start? There are hundreds of different options on the market for you to choose from across all price points, quality ranges, and sizes. This can make it difficult to find what you need, especially if you don’t know what you’re looking for yet (or what your car can support).

If you’re lost on where to start, you’re in luck – in this guide, we’ll walk you through how to determine the right size speakers for your car, as well as other features you might want to look out for.

Speaker Type: Cabinet Vs. Integrated

Before you go any further, do you know what kind of car speakers you’re looking for? If you’re looking to install large cabinet-style speakers with custom housings in your car, you can, in theory, go as large as you want. Of course, the size of your trunk (or whatever other places you install them) is your upper limit, but since you don’t need to fit your speakers to the size of your car’s factory speakers, you have more freedom to choose.

However, if you just replace the speakers that come integrated into your car’s body, the end result is more compact and attractive but no less functional. Rather than needing to find a place for an obtrusive speaker box, you can place these speakers in the same hole where your stock speakers used to be. You’re more limited by size, but there’s still a wide range of options to choose from.

Which Speakers Does My Car Use?

There’s an entire process of deducing which speakers your car was designed to use. If you have your car’s documentation somewhere, you may be able to find that information easily. However, if you have an older car or lack your documentation, you might need to do a little research.

If you’re lucky, you may be able to find this information with a quick online search, especially if you have a car that’s popular for aftermarket upgrades. However, if that fails, you’ll have to go in and measure things manually.

The best way to do this is to remove your car’s stock speakers and measure them. This will give you a good idea of what speakers will fit your new car. Some of the most common sizes for car speakers include:

What Do the Numbers Mean?

While knowing the above are “standard” stereo sizes is all well and good, it won’t help you much if you don’t know how to measure your own speakers. While the numbers above might help you start your search, they don’t mean much in reality! A six-inch by nine-inch speaker may not actually measure six by nine inches, for example.

The most important thing for you to do is to measure your car’s current speaker size before moving on. If you don’t feel comfortable doing this, you may be able to take your vehicle to see a customization expert. They should be able to help you determine the size of your factory speakers and what to replace them with.

However, if you have a bit of time and inclination, you can measure your speakers yourself very easily.

Measuring Your Speakers

Before you can remove your car’s stock speakers, you’ll need to expose them carefully. Plastic covers protect many stock speakers, and you may have to move some of your car’s lining temporarily, too. This project can be easy or difficult depending on your car’s make and model; if your speakers are difficult to access, a professional’s help may be useful.

Once your stock speakers are fully exposed, it’s time to remove and inspect them. However, always be sure to disconnect your car’s battery before unscrewing any components! Since your car’s speakers are connected to your car’s electrical circuits, you could be shocked in the process of removing them if you don’t take this precaution.

Next, you’ll need to find a screwdriver. Your car’s stock speakers are probably secured to its body with simple screws, though whether those screws are Phillips screws or flat screws can vary by car make and model.

After you’ve removed the screws holding your speaker in, you may find that your factory speakers are also held in place with glue. If this is the case, you’ll need to gently pry them out with a screwdriver or other similar tool. Adhesive remover may be helpful here, too, though it may not help much depending on how much adhesive you can reach.

It’s best only to do this step yourself if you don’t plan to save or reuse your factory speakers since they could end up damaged in the prying process. If you want to keep them, it’s always a good idea to seek a professional’s help.

Once you have the speaker free, you’ll need to disconnect some wires, and then you’ll be free to measure its size. The four measurements you’ll need to take to get a good idea of your stock speaker’s size are:

  • The speaker’s diameter
  • The baffle size (or cutout diameter)
  • The speaker’s depth
  • The mounting height

The first (and arguably most important) number you want to measure is the speaker’s diameter. If your speaker has protruding mounting brackets, measure from the outside of the bracket directly across the speaker’s middle. This is your diameter.

Contrary to what you might think, your speaker’s diameter isn’t measured based on the speaker cone itself. Most speaker manufacturers include the mounting brackets and shielding in their diameter measurement, so you should do the same, too.

The next number you want is the speaker’s baffle size (or cutout diameter). This can be a bit difficult to measure, but the best way to do so is to flip your speaker upside down and measure the diameter from there. To measure the baffle cutout, measure the part of the speaker where it starts to go from a flat circle into a cone shape. In other words, this is the measurement of the widest part of the back of the speaker (not including the shielding and mounting brackets).

Of course, you want to measure the depth of your speaker, too. It’s all well and good to have a speaker with the correct diameter, but if you misjudge the depth, you could have a speaker that still doesn’t fit! The depth of your speaker, of course, is from the front to the back.

The final measurement you should take is your speaker’s mounting height. Your speakers’ mounting height is based on how much your speaker protrudes when it’s attached to your car. The shielding around the speaker itself and the mounting brackets can protrude, but the tweeter in the center of the speaker (if you have one) can do so, too.

This might not seem like an important step, but it’s surprisingly essential, especially if you have a smaller car. If your speaker protrudes too much, it might bump against your seats, against your door panels, or even against you while you drive.

Which Size Do You Need?

Now that you have the speaker size that your car can natively support, you can start shopping for options. However, before you start narrowing down your results, keep in mind that you can always add an adapter to make small speakers fit, but you can’t always make speakers that are too big fit easily.

If you’re set on a large speaker that won’t fit in the old speaker slot, you can always construct a custom speaker enclosure. However, this is an advanced technique that you should only attempt if you really know what you’re doing since it requires altering your vehicle’s interior. If you don’t have experience with this, it’s smart to seek a professional’s help.

However, there are a few other things you should keep in mind about your car’s speakers, too. Just like all vehicles are unique, there are all sorts of speaker shapes out there, too. Your vehicle might use non-standard-sized speakers, such as oval-shaped speakers, instead of the usual round style. Make sure to keep an eye out for quirks like this.

Finally, it’s always a good idea to check the rest of your car for differently-sized speakers. It’s common to find smaller speakers in the back doors of vehicles, for example, as compared to the front. If you hope to replace all of the speakers in your car, make sure to check these first, as you could end up with some speakers that don’t fit if you buy all one size.

If you decide to shop for speakers in person – which is always a good idea, if possible – make sure to bring your disconnected speakers with you. This way, you can compare your factory speakers’ size to any new models before you walk away with them. This’ll help lower the chance that you’ll purchase a set that doesn’t fit.

Helpful Resources

Some companies offer “fit my car” tools online to help you pick out speakers that are known to fit in your car make and model. However, use these tools sparingly, as they may be branded to only one company, or they might not have many results for your specific car.

However, it would help if you considered looking at other online resources for car speaker sizes, too. Online forums and published guides can sometimes have stock speaker measurement databases as well as lists of speakers that fit specific car models.

Other Considerations

There are a few other things you might want to keep in mind while choosing your car’s new speakers. Firstly, keep in mind that a perfect speaker size match might not exist for your vehicle. If your car’s manufacturer decided to make its own proprietary speakers for your car to fit into a small or strangely-shaped space, you might be forced to modify the area you have.

And secondly, keep in mind that your speaker’s size isn’t all that has to match. The wattage of your speakers should match the rest of your vehicle or your amplifier, and you should consider other performance-based parameters of the speakers, too.

After Measuring: Choosing Your Favorite Speakers

While you might know what size speakers you need in your vehicle now, you’re not completely done yet! We listed a few other things to consider in the paragraph above, but there are far more things you’ll want to take into consideration before taking the plunge on new speakers. We’ll address some of them in the following paragraphs.

Sound and Space

The whole point of a set of speakers is to make your music and media sound better in a given space. As you may know already, different speakers are designed to work in different areas. Some speakers are designed to make the most of a small space, while others sound best in larger vehicles.

Make sure to consider how your speaker will sound in your car before you buy it. You can figure this out with a little research and some information about the speaker’s specifications. Online research is particularly useful for this, as are reviews and videos from other consumers.

If you have the opportunity to test some speakers in your vehicle before committing to them, do it! Otherwise, you’ll have to make your best guess based on the resources available to you. And, if all else fails, a professional customization shop may be able to help you create a custom rig, or they might have some recommendations for you about what sounds best in your car.

Some specialty stores and businesses have “demo cars” that help you get an approximation of what your speakers will sound like, and others will have display boards that let you test performance. While these display boards won’t give you the same sound and feel as a car would, it’s better than not testing the speaker at all before you purchase it.

If you do have the opportunity to test some prospective speakers in person, try and bring your own music if you can. While you can listen to any song or media on these test speakers, you’ll have a better idea of performance by listening to music you’ve heard before.

Speaker Type: Component or Coaxial

As you might expect, car speakers don’t just vary by power rating and size. Speakers come in different configurations, too, and these configurations can affect how the final product sounds and performs. Two of these types that you’re likely to run into are component speakers or coaxial speakers.

Essentially, when it comes to speakers, different parts are designed to handle different frequencies in the sound. You’ve probably seen treble, midrange, and bass settings on an equalizer before. Component speakers separate these settings to different speakers. For example, you might install the treble speaker (or tweeter) in the A-pillar of your car and the midrange speaker in the door.

A coaxial speaker, on the other hand, brings these pieces together. The two components’ drivers are separate, but the tweeter might be mounted to the midrange speaker itself. This saves space in your vehicle, but it might not create the same surround sound feel that separate speakers can.

Additionally, the most expensive component speakers tend to be higher-quality than the most costly coaxial speakers. However, at moderate and low prices, the quality and effect are very similar, so this may not factor into your decision at all.

Speaker Cosmetics

Last but not least, you can’t forget about your speakers’ looks when installing an aftermarket setup. Many consumers care about the appearance of their speakers just as much as they care about their quality. While this may or may not matter to you, especially if you plan to cover your new speakers, it’s something you may want to keep in mind.

Car speakers, especially those designed to be exposed, come in all sorts of colors and designs. Some of them are designed to be showpieces just as much as functional speakers. These speakers can often be more expensive, but that’s to be expected since you’re getting form as well as function.


In the end, replacing your car speakers isn’t too hard, though you should do it carefully. The complicated part is finding new speakers that fit well in your car. Due to the lack of a unified measurement system among car speaker manufacturers, even if you think you might be getting the right thing, you still might end up with the wrong product if you don’t do your due diligence!

However, if you follow the measures we’ve outlined in this guide, such as carefully measuring your stock speakers before purchasing new ones, you should be able to replace them successfully. Of course, if you ever run into trouble, feel unsure, or don’t feel confident, professional help is always available.

Brett Gordon

The engine behind editing at DigMyRide and the brains behind its build. During the day, Brett is a thirty-something dude from SoCal climbing the corporate ladder, but by night, he spends his time contributing to the online world of automotive tech & trends.