The Big Guide To Car Speaker Sizes (Plus Great Installation Tips!)

If you’re looking for a great guide to car speaker size options and what you need to know, you’re in the right place!

To help you, I’ve put together a detailed guide with examples of each standard peaker size, what you need to know, and very helpful installation tips based on my car audio installation experience.

The big list of car speaker sizes (photos and what to know for each)

List of car speaker sizes section image

Here’s a pretty comprehensive list with the basics to know. Be sure to read my installation tips in the last section to help you avoid headaches!

When buying new speakers, bear in mind the following:

  • Although there are common speakers sizes, each manufacturer uses slightly different dimensions during manufacturing. Always be sure to check and don’t assume they’re all the same.
  • The speaker diameter measurement for the hole will usually fit a standard size opening. However in some case it may be very tight or even require cutting the vehicle’s metal a bit. A speaker spacer ring may help avoid the need for that.
  • Speaker brackets are helpful when the mounting tabs on your new car speakers don’t quite match the existing hole spacing. You can use metal car audio installation straps to help with this (they’re easy to bend/break off and they’re cheap).

1. 3.5 inch speakers

3.5 inch car speaker example and info image

3.5 inch (89mm) speakers are commonly used most often for dashboards and tight spaces where larger speakers can’t fit. Aftermarket speakers are typically coaxial speakers with a tweeter and woofer cone with a frame with 2 screw mount tabs.

Unfortunately, they’re terrible for bass for a number of reasons:

  • Very small woofer cone (can’t produce large bass waves).
  • Usually installed with no sealing, meaning they’re not in a good enclosure.
  • Lower power handling than others.

While they’re not good for bass or midbass in music, they are good for highs (treble) and midrange as part of a speaker system with woofers and/or a subwoofer to fill in the gaps. Power handling tends to range about 15W to 30W on average, depending on the model.

example of a 3.5 inch car speaker installed in a dashboard

Image showing example of a 3.5 inch speaker mounted in a truck dashboard.

3.5 inch car speakers have a hole mounting size of about 3 1/4″ wide. Always be sure to check the mounting depth before buying a replacement and be aware that some require some creative work to make the screw tabs fit.

2. 4 inch speakers

4 inch car speaker example image with notes

4 inch speakers are similar to their smaller 3.5 inch siblings but offer a bit better sound. You can find 4 inch car speakers sold in several styles:

  • Coaxial (tweeter and woofer).
  • Woofer or midbass only.
  • As a component speaker set with a separate crossover.

Power handling tends to average about 25W to 45W depending on the speaker and many offer some great tweeters (silk dome, metal dome, etc.).

While 4 inch speakers are also often mounted in a dashboard from the factory and have no real enclosure, they’re often somewhat better performers than 3.5.” There are also often more quality speakers to pick from as well.

example of 4 inch car speakers with 4x6 inch adapter plates

As they use a small cone, they’re not good for bass frequencies or midbass near the lower end. However, the midbass and vocals can have decent low-end coverage if they’re mounted in a good enclosure (and it’s one recent many home stereo speakers use a 4 inch successfully).

Like others, you’ll get the best sound by complementing them with bigger speakers if possible and especially subwoofers for the bass they lack.

4 inch component speakers can really sound good as part of a complete system. They can also be use with adapter mounting plates to substitute other sizes like 4×6″ or 5.25″, giving you more options.

3. 5.25″ (5 1/4″) speakers

example of 5.25 inch car speakers

The good news is that 5.25 inch (5 1/4″) speakers are a bit better at midbass than their smaller counterparts like 4″ and 3″ speakers. They’re also one of the more popular and common sizes, meaning you’ll have a ton of options when shopping.

5.25 inch speakers are available in coaxial, midrange, or midbass only, and component sets. They’re commonly factory installed in front and rear doors as well as the rear deck or rear side panels.

example of 5.25 inch car speakers installed in rear deck of car

Image of rear speakers installed in the rear deck.

This size is also often a great compromise between cost and performance. You’ll also find them offered with higher-quality tweeters and woofer cones for enhanced sound clarity. Power handling is about 25W to 55W on average.

If you’ve got a set of this size you’ve got handy or found a pair you’re wanting to install, one option is to use a speaker adapter to use the in place of a bigger size. (I’ll cover that in more detail later)

4. 6 inch and 6.5 inch (6 1/2″) speakers

6.5 inch and 6 inch car speaker examples with notes

Although 6.5″ speakers are much more common than 6″, I’ll include them here as they’re often a good replacement choice. 6.5 inch speakers are some of the most popular and are one of the largest sizes available prior to 6×9″ or similar models.

6 & 6.5 inch speakers are pretty good for midrange, midbass, and even some decent lower-end bass depending on the installation and car audio system. Factory-installed speakers of this size are located in the front or rear doors as well as the rear deck.

They’re available in a great variety of options (mostly for 6.5″):

  • Component sets, both separate and “stackable” component options.
  • Midbass or midrange drivers.
  • Woofers and subwoofers.

One of the best replacement options you can use is door 6.5″ woofers with tweeters mounted high in the doors or on the dashboard.

6.5 inch car subwoofer options

6.5 inch car subwoofer and woofer examples

Subwoofers of this size can’t produce the bass of a “real” subwoofer (larger 10″ or 12″, for example) but can sound great when used well. Some 3-way systems use component speakers and a 6.5″ subwoofer or woofer to cover the low frequency response smaller speakers can’t provide.

They normally have much higher power handling, more speaker impedance options, and a lot more bass than a standard 6.5″ could. They’re commonly used fairly often in 8 ohm home subwoofers as well.

5. 4×6 inch coaxial and plate speakers

4x6 inch car speaker examples with information

4×6 inch speakers have a larger cone surface area than 4 inch speakers, meaning they can produce more sound from a relatively similar space. However, since many are mounted in a dashboard or rear pillars from the factory they’re often in terrible enclosures and won’t produce any real bass.

One benefit unique to this size is that some are available in a “plate” style which uses a component speaker style design with separate drivers. You can also use a 4×6 adapter to use a 3.5″ or 4″ in place of a 4×6. This is also a great way to install only tweeters for upgraded speaker systems where you’re using a component set with larger speakers installed elsewhere.

Expect similar power ratings to 4″ speakers (about 25W-35W or so typically).

example of 4x6 speaker installed in a Jeep dashboard

Example showing a 4×6 inch plate speaker installed in a Jeep dashboard.

One thing to note is that 4×6 speakers sometimes have a very closely-fitting grill over them, meaning speakers with tweeters sticking out further cannot be installed properly. It’s important to check the height before buying new car speakers.

I’ll cover this in more detail later.

6. 5×7 inch speakers

5x7 inch car speaker example with measurements

5×7 inch speakers are common in doors, rear side panels, and the rear in hatchbacks and sedans. They’re somewhat smaller than 6×8 or 6×9 speakers but offer a big cone size than 6.5″, meaning they can produce more bass & sound in the right environment.

5×7 inch speakers aren’t very common but you’ll come across them from time to time. Some average power handling ratings are about 30 watts to 50 watts. Unlike 4×6 speakers, its plate speakers aren’t much of an option as while they do exist they’re fairly rare.

Example of 5x7 inch coaxial car speaker installed in car door

An example of a 5×7 inch coaxial speaker mounted in a car door.

However, it’s easy to find 5×7 installation adapters. You can install 6″, 6.5″, or 5.25 inch speakers if you like and mount component speakers in place of a 5×7 as well. Expect to pay about $45 to $100+ for a pair of coaxials depending on the quality.

7. 6×8 and 6×9 inch speakers

image showing examples of 6x8 inch and 6x9 inch car speakers with measurements

As they’re so similar I’ll cover both here. One of the largest speakers sizes you can buy, a 6×9 inch speaker offers a fairly large cone size like other oval speakers. Since it’s not perfectly round but takes advantage of length, the total amount of air moved is significantly larger than a 6 inch or 6.5 inch which fits in a similar space.

Good 6×9 speakers can put out enjoyable bass for good sound in the right speaker enclosure. Don’t expect subwoofer-level bass, but still good nonetheless. They’re also good for high-power systems and you can even buy 6×9 component sets as well.

example of 6x9 car speakers installed in a vehicle rear deck

Example of 6×9 speakers installed in the rear deck of a car.

6x9s are also a great choice for recreational vehicles, boats, and can be used in small pre-made speaker enclosures for vehicles like those where there are no speaker openings. Another great idea is removing them before storage (or before parking for a long time, in the case of a convertible vehicle) to prevent theft.

6x9s also have adequate power handling, with about 50W for typical coaxials and up to nearly 100W or so for high-performance models.

example of 6x9 inch car speaker enclosures

Shown: 6×9″ speaker enclosures that allow you to use them anywhere. Great for vehicles like Jeeps, boats, big rigs, and more!

8. 4×10 inch speakers

example of 4x10 inch car speakers with measurements and cutout size

4×10 speakers are a somewhat unique type in that they’re very oval (long) in shape and are designed to fit in areas where there’s more length space than width. They’re also not very common.

You’re likely to find them in some vehicle dashboards, rear upper pillars in some truck cabs, and rear areas like that in other vehicles. They’re somewhere close to 4×6 or 5×7 inch speakers in their output.

In other words, don’t expect much bass – but they’re adequate for midrange and treble.

4x10 inch car speaker in dashboard installation example

Image showing a 4×10 inch speaker installed in a truck dashboard.

Since they’re less common your shopping options will be more limited, but you should be able to find some good quality coaxials that sound nice. Since 4x10s are often installed from the factory in locations where there’s no adequate sealing the performance will be very limited due to the lack of an enclosure like a lot of other speakers.

Power handling tends to be somewhere around 25W to 35W or so.

Coaxial vs component speakers explained

Component vs coaxial speaker comparison

What are coaxial speakers?

What are coaxial speakers diagram & parts labeled

Coaxial speakers are a 2-way full range speaker design using a woofer and a tweeter with basic crossover built into a single assembly.

Most provide a woofer cone with a separate tweeter for good full-range sound and frequency coverage, unlike very simple single-cone speakers.

You can think of coaxial speakers as a compromise between single cone speakers (the cheapest speaker, with poor sound) and a better-performing component speaker system. They’re very popular as they offer good sound while keeping costs down.

Coaxial speakers have some nice advantages:

  • Easy sound upgrade: they’re a drop-in replacement for older factory-installed & bad sounding single cone car speaker types.
  • A wide range of performance & price options for buyers: different levels of tweeter quality, crossover design, cone materials, higher power ratings, and so on.
  • They’re easy to find and very popular – in fact, they’re the most popular car speaker upgrade and easy to find.
  • Affordability: reasonably good ones can be found for around $25-40 and up. Very good quality coaxials are only about $50-$65 or, while high-end models with great performance can reach over $100 USD.

What are component speakers?

Component speaker sets are made up of separately mounted woofers, tweeters, and crossovers that deliver better sound quality than coaxial speakers.

Component speakers usually include a better quality tweeter and woofer along with a more effective crossover. They may also include features such as tweeter volume reduction (dB jumper) and additional wiring configurations.

Some even are designed in such a way that they can be assembled together like a standard coaxial speaker for installation convenience, too!

Component speakers offer:

  • Better frequency response and sound accuracy – even entry-level component car speaker sets can have really great sound quality!
  • Tweeters with a more rigid and high-performance design: silk, aluminum, ceramic, or other special dome materials are common.
  • More power handling – often 75 watts RMS, 100 watts RMS, or more.
  • -12dB per octave crossover slopes (or greater) versus the standard -6dB/octave crossover used on others.
  • Better crossover component quality and performance (-12dB/octave is very common).
  • The ability to mount the tweeters at a line-of-sight listening height and angle for better stereo imaging with music playback.

However, it’s important to note that the installation process is harder than for others and can require custom fabrication for the tweeter mounts. You’ll also need to mount the crossovers as well – ideally away from moisture and fairly close to where the speakers are mounted.

They’re also a bit more costly, too, as many component sets cost around 1.5x to several times more than coaxials of the same size.

TIP: If you’re looking for excellent sound then component speakers with an aftermarket amplifier are what you need. Coaxials will benefit from using the great power and quality sound an amplifier can provide, too!

4 CRITICAL things to know before buying and installing speakers

image about avoiding car speaker installation problems

There’s a number of potential problems you might not be aware of when you’re thinking about upgrading or replacing car speakers. Based on my installation experience here are some of the biggest I’ve run across and that hopefully will help you prevent some huge headaches.

1. Speaker depth and magnet size

diagram showing factory vs aftermarket car speaker installation depth problem

One big issue is factory vs aftermarket car speaker magnet sizes. Factory installed car speakers often have a shorter height and smaller magnet with a limited installation depth due to dashboard or body parts that block the bottom.

In many cases new speakers have a taller height and/or larger magnet, meaning they may not fit into the existing mounting depth. Be sure to measure car speaker fit dimensions with a ruler before buying anything.

2. When they don’t align with the original holes

diagram showing factory vs aftermarket car speaker hole mismatch installation problem

Many vehicles today have a mounting hole pattern or use a speaker frame that doesn’t match up with aftermarket 4 hole patterns. In that case, you’ve got a few options so being prepared beforehand is extremely helpful.

Here are some options:

  • Use a speaker adapter ring or plastic plate.
  • Use self-tapping screws and a cordless drill to easily add screws through sheet metal with the new car speaker’s mounting holes.

example of a 3/8 inch pan head #8 self tapping screw

Self-tapping screws can make your installation work a lot faster and easier as they avoid the need to drill holes or change drill bits. You get the benefit of both drilling a hole and a screw at the same time!

3. Factory speakers built into a frame or in a non-standard mount

example of a factory car speaker built into a mounting frame

Some factory speakers can’t be replaced directly or easily because they’re mounted in a plastic frame or housing. Some are even built into it and when they’re removed you’ll have a hole that’s too large for your new ones!

image showing examples of car speaker installation adapters for changing speaker size

Be prepared – check to find out if you’ll need a car speaker installation adapter.

These are typically made of ABS plastic and provide a standard size opening along with mounting holes to match stock speaker measurements.

Some are made of medium density fiberboard (MDF) or you can even make your own out of MDF or wood. I recommend buying ready-made adapters as it’s a lot less time and effort for only a few dollars.

4. Tweeters that are too tall for factory grills

diagram showing factory vs aftermarket car speaker tweeter height installation problem

This is an especially big problem for many trucks with dash speakers, pillar speakers, and in some cars or other vehicles as well. Just as you’ll find aftermarket speakers with a taller height & bigger magnet than the originals, many also have a better quality tweeter but a taller height.

The problem with that is sometimes it’s impossible to put the original speaker cover or speaker grill back in place due to too little space. Be sure to check the originals and the grill clearance vs the speakers you’re considering buying.

How to use a different size speaker in place of the originals

car speaker size adapter example image

There’s some great news if you’d like to (or have to) install a different car speaker size than the originals. A speaker adapter will make this easy in most cases.

These fit in place of the original speaker (often with the same screw hole dimensions) and provide a standard car speaker size hole to mount your replacement speakers. Some also include additional openings that can be scored with a utility razor and cut in case you’re using a different size.

What if the originals aren’t a standard speaker size?

In that case you’ve got a few options:

  • Use a regular speaker adapter and mount it in place of the originals by using self-tapping screws or brackets as needed. That’s because the original hole spacing is usually different.
  • Speaker spacing rings can be used to help make up the difference if it’s close. You may need brackets to mount them.

About the author

Marty is an experienced electrical, electronics, and embedded firmware design engineer passionate about audio and DIY. He worked professionally as an MECP-certified mobile installer for years before moving into the engineering field. Read more »

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