What size car speaker should I buy?

One of the most common questions we get asked as car speaker fanatics helping out friends is “What size speakers do I buy for my new system?” We think this is an excellent question, and we put together this article to tell you about car speaker sizes and the advantages/disadvantages of them.

Check Your Manual

Most modern car manufacturers understand that charming individuals such as yourself will want to replace their less-than-adequate factory speakers, so they include speaker sizes in the manual. If you are looking for quick installation of some full-range speakers that will provide a significant difference for less money, this is an easy way to change out your car speakers. Keep in mind, you will be required to use the same size speakers as originally came in your car if you choose this method, and component speakers might be out of the question.

Why Car Speaker Size Matters

It is important to understand why there are different car speaker sizes available for your car audio system. Speakers at different sizes reproduce different frequencies. For example, a tweeter which is normally 1-2 inches in diameter, reproduces high frequencies without pain, but you wouldn’t receive bass-heavy notes from this speaker.

If your car currently has full-range speakers and you are looking for easy installation, you should purchase high-quality full-range speakers to replace the ones already in your car. If you are looking for a dramatic increase in speaker quality, you should consider component speakers. Keep in mind that you will need an amplifier for this conversion, and you will most likely need to purchase new Tweeters and a subwoofer for your system for best results.

Different Car Speaker Sizes


This is the smallest size available for car speakers. The usual size they come in is about 1-2 inches. They produce great high range sounds and are best installed in the A-Pillar if the windshield. If this is your first audio installation, and your car didn’t come from the factory with a spot to mount tweeters, you should consult a professional to help you install these. Many cars have airbags in this location, and that can be very dangerous for a DIY-er to attempt. You should only install these speakers if you have a component system or you are switching over to a component system.


These speakers are available in size range from 8 to 15 inches. These speakers provide you with a low-end bass frequency range that is very hard to accurately reproduce by a smaller speaker. It is most likely that you will need to install an amplifier to run these speakers, as their large size requires a lot of energy. We put together a guide on amplifiers here.

Size 6″ x 9″

If you are not ready to commit to a dedicated subwoofer, or perhaps you have a serious subwoofer that needs some support on the higher ranges, this is a great speaker to install for mid-range bass. Many vehicles already have these mounted in the door panel, so you will have an easy time replacing these if your car happens to be one of them. Check your manual to see if this is the case. The size produces a louder and clearer sound than 5″ speakers for bassy notes.

Size 3.5″

These speakers are mid-range to high-range speakers that are best suited when you have tweeters to take care of the high range but want a crisp high middle range to support the sound signature of the tweeters more fully. We recommend going for these speakers when you have 6×8 or 6×9 inch speakers to handle middle-lows.

Size 5″

5″ Speakers are better for when you need a great middle range but don’t have the ability to put in middle-high and middle-low speakers. The treble in this size is crisp and produces a solid bass even with this 5-inch size, but have a more specialized separation between the middle-high and middle-low speakers will provide a better overall sound quality. You will need to look at your mounting space to see what your options are.

Size 5.25″

This size is the most purchased size because of its great ability to adapt when installing into any car. It is typically pretty easy to retrofit these speakers into doors and for them to provide a crisp middle-low and middle-high. It’s not as good as separate speakers, but the sound received from a 5.25-inch speaker will be very good regardless.

Size 6.5″

These are typically great middle-low and low-high speaker companions. You should pair these up with a powerful subwoofer and a powerful mid-high speaker and you will be very happy with how full your speaker setup sounds. These are typically more expensive, but they have great sound signatures and great brands building them.

5″ x 7″ / 6″ x 8″

Although these speaker sizes are less common, you might still want to install them if they will fit into the standard mounting of your car. Otherwise, we recommend the Tweeter, Mid-high, Mid-Low and Sub setup, which these speakers don’t often times fit in the mold.


Amazon has not replaced car audio shops (yet!). We recommend that you head over to the car audio shops and take a look around the selection at speakers that will fit your car with minimal installation. Play with a couple of speakers together to get a full perspective of how they will work together. Once you have decided on your sound signature and the sizes you want to go with, check out some of our reviews on the best speakers of that size and install them for maximum enjoyment. Hopefully, this article was helpful to you to decide on what car speaker sizes you will be looking at!

Frequently Asked Questions

How is a car speaker measured?

Car speakers are measured in distance between frame screws diagonally. You can measure your current car speakers by measuring the distance between diagonal screws for best results.

How is a car speaker measured?

Car speakers are measured in distance between frame screws diagonally. You can measure your current car speakers by measuring the distance between diagonal screws for best results.