Wondering what size speaker wire you need? You’re in the right place!
In this guide, I’ll show you the proper gauge and type of speaker wire you need. I’ll also cover a lot more, too:
- Simple & quick rules of thumb for speaker wire size if that’s all you need to know.
- Speaker wire gauge and the American Wire Gauge chart explained.
- Understanding copper clad aluminum (CCA) vs pure copper wire so you don’t get ripped off.
- Solid vs stranded wire .
Contents
General tips: What size speaker wire do I need?
- For most low power home or car speakers (not subwoofers) 18 gauge (18AWG) is fine. 18AWG wire is good for about 50 watts for 4 ohms and 100 watts for 8 ohm loudspeakers up to 50 feet (15 m) or 100 feet (30 m) respectively.
- For higher power systems or longer lengths, 16 gauge is a great choice.
- For longer lengths (50-100ft)/(15-30.5m) you’ll need to go up 2 gauges (14 ga.) to avoid losing power. Very long lengths of speaker wire lose a bit of power over the long distance due to resistance. Using larger wire can help reduce or avoid this. (Use my speaker wire calculator to make it easy)
- A higher speaker impedance value (ex.: 6 or 8 ohm speakers) draws less current (lower amps) than lower impedance speakers. Therefore you often can use a thinner wire for them as you’ll see.
Simple “everyday” wire size table
| Wire Size | Recommended For |
|---|---|
| 18 AWG | Car and home speakers up to 25 ft with average power levels (50W RMS and below). |
| 16 AWG | Longer speaker runs for car & home stereo speakers or short runs under 20 ft for 75-100W. Moderate power subwoofers (under 225W) with short lengths. |
| 14 AWG | Long (100ft+) speaker runs or higher power applications such as high-power 2 or 4 ohm subwoofers with a short length. |
In most cases for everyday listening at medium or low power levels (50W RMS or under), 18 gauge (18AWG) wire is what you need.
It’s a good compromise between price and power handling as it’s usually affordable and easy to find.
How to find the correct size wire for ANY length or speaker system
The correct gauge speaker wire you need is based on 3 things:
- Your stereo or amplifier’s power output.
- The speaker’s impedance (Ohms) rating – also called the nominal impedance.
- The cable length needed for your speaker system.
However, I’ve made it easy for you: You can use my speaker wire size calculator or speaker wire size chart sections provided below.
SPEAKER WIRE GAUGE CALCULATOR
My speaker wire gauge calculator will recommend the right speaker wire gauge based on the power, speaker Ohms, and the specific length you need. This is different from the speaker wire size chart section below that provides lengths based on the speaker Ohms only and doesn’t need power ratings.
You can play around with different power amounts, lengths, and speaker Ohms to find the best speaker wire gauge for your audio setup and avoid spending more money than necessary.
HOW TO USE:
- Enter the following:
- The wire length you need. This can be whole or fractions (5 ft, 2.6 ft, etc.).
- RMS/continuous power for your amp or stereo. (Do not use “peak” or “max.” power ratings.)
- The speaker impedance in Ohms (Ω).
- Touch the button to get the results.
The wire calculator will output:
- The smallest wire size with 5% or less power loss for both copper and copper-clad aluminum (CCA) wire.
- The power loss across the wire, in Watts, at maximum power output.
SPEAKER WIRE GAUGE CHART
The chart and tables above are handy if you aren’t sure about your stereo or amplifier power. You can estimate the length of wire you can use without losing a lot of power (at maximum stereo or amplifier output) knowing only the speaker Ohm rating.
Both copper wire and copper clad aluminum (CCA) wire charts are provided. Because aluminum has a lower conductivity than copper (higher resistance per foot), the length will be shorter than for real copper.
Note: Be sure to check my additional tips further below as they can help you save money.
Choosing a speaker wire gauge for long distances
What if you need say 50ft or even 100ft of length? In that case, a general rule of thumb is to double the size by choosing a wire thickness 2 sizes up from what you would use for shorter distances.
The gauge number (the electrical conductor size as per wire standard charts) increases or decreases by an even number (by adding or subtracting 2) as odd numbers aren’t commonly used.
Example: 18AWG wire will lose about 4 watts at maximum power if it’s 50ft long. To avoid this when moving from a shorter wire length, we can pick a speaker cable 2 sizes up: 18 AWG -> 16 AWG -> 14 AWG.
Tips on using smaller speaker wire and saving money
As real copper wire is more expensive these days and because most people don’t drive speakers at full power, here are some tips to keep costs down:
- If you rarely use your amp or stereo output above 50%-60% power, you can go down one wire AWG gauge. This is because you’ll never reach the wire’s current capacity if you don’t use maximum power.
- Have extra wire you’d like to put to good use? You can double-up or even triple-up smaller gauge wire to get the same gauge as a thicker wire size. (Example: using two lengths of 18AWG you have lying around in parallel to approximate 16AWG wire).
- For surround sound and center channel home theater speakers, you shouldn’t spend a lot because their power needs are usually fairly low.
Is oxygen free speaker wire worth it?
No, oxygen free pure copper wire will not deliver any noticeable improvements in sound or power. It’s not worth spending more money on it.
It’s a great marketing feature for retailers but the data shows that there’s an amazingly small difference in performance. Paying more is a waste of money. As long as you’re using a good quality wire with the correct gauge you’ll be fine.
The electrical signal will not have any measurable difference at the speaker end.
It is true, however, that real copper wire is better than copper coated aluminum wire as I explain later.
What gauge is speaker wire? (Wire size and wire gauge explained)
Speaker wire doesn’t have just one size (gauge) – it’s standardized and based on the American Wire Gauge (AWG) chart which lists standard sizes using a number.
Less commonly known as the Brown and Sharpe wire chart, the American Wire Gauge chart has been around since 1857. It specifies sizes, each with a given circular area of the electrical conductor size, its resistance per foot or meter, and some other specifications.
Likewise, each AWG wire gauge has an electrical current capacity (how many amps it can handle, also called ampacity sometimes).
The AWG wire chart uses a numbering system in which thicker cable has a smaller number. Likewise, a larger number is used for smaller wires with fewer conductors.
Speaker impedance and power vs the correct gauge wire
When an amplifier supplies an audio signal with a given voltage output, speakers with a lower impedance draw more electrical current (higher amps) than higher impedance speakers. This can make a difference in the wire size you need based on the length and power carried to audio speakers.
Higher amps require a larger conductor size (thick wire) just like for power wire. By comparison, thicker speaker wire has low resistance and therefore less power lost across it at high power levels or a long cable run.
Most speaker wire sold today is made up of two conductors attached as a pair with one marked as the positive; they’re essentially the same as stranded power cable paired together. The gauges available range from about 20 gauge to 10 gauge, with 18 gauge being one the most popular.
Thin wire such as 20AWG or 22AWG isn’t very common but occasionally can be useful for lower power speakers.
Stranded vs solid conductors
All speaker wire sold is stranded, meaning it’s made up of a bundle of 16-60 or more very fine copper conductors. Solid wire, however, has only one conductor. In terms of audio, it’s fine and the sound quality is the same.
You may have heard of the skin effect in some conductors which becomes more of an issue at higher frequencies but that’s well above the 20 to 20kHz audio range so it’s not something to worry about.
Stranded speaker wire design
For stranded types, a thicker wire gauge uses more conductor strands with each strand being larger than those in a smaller gauge wire. Some types simply use more very fine strands to enhance flexibility during use but will still maintain the same total conductor cross area and current carrying capacity.
Why stranded speaker wire is preferred over solid
Stranded wire has a big advantage over solid in that it’s very flexible and not prone to breaking under stress. It’s also easier to strip the insulation to bare wire with a wire stripper. It’s also easier to work with if using spade connectors or inserting it into a crimp connector.
Since solid core is used for home and industrial electrical wiring, you might be tempted to use some leftover house electrical wire for your speakers. There’s no technical reason you can’t use it for audio but smaller gauge solid wire can develop stress cracks over time due to vibration in installations like a vehicle, for example.
Solid core wire isn’t easy to deal with in situations where you’ll need to go around curves like around car seats or tight spaces.
How much wire do you need?
Buying & using speaker cable is definitely one of those cases where the old advice “better to have too much than not enough” applies! You don’t want to run out because you didn’t plan ahead.
It’s always best to measure and be sure – and overestimate what you need to be sure you don’t run short.
To figure out how much speaker wire you need, my suggestion is to use one of the following:
- A tape measure
- A long length of string to run
Be sure to try to take curves & bends into account but don’t worry about getting it exactly right. Measure the distance and then add a few feet (an extra 2 feet or so is good) to account for curves and other little things that add up.
A tape measure works well and so does string or rope you can place along the path where the wire will go.
Mark the length, then measure it. I like to add at least 1 foot of length for each wire section for home stereo use and 2 feet each for car stereo installations to play it safe.
Figuring out how much wire to buy
When it comes to buying speaker wire, one thing to know is that it adds up fast! Here are two examples to show what I mean:
Home stereo example:
- Front speaker lengths measured: 2 x 6 ft
- Rear speakers measured: 16 & 22 ft
Total wire needed: 6 + 6 + 16 + 22 = 50 ft (15.2m)
Car stereo example: Running wire from the dashboard head unit to front door speakers and to rear deck speakers.
- Front speaker lengths measured: 2 x 8 ft
- Rear speakers measured: 16 & 20 ft
Total wire needed: 8 + 8 + 16 + 20 = 52 ft (15.9m)
Speaker wire is normally sold in rolls such as 25ft, 50ft, and 100ft, although some retailers offer it by the foot as well.
Precut lengths are also available sometimes, too. Those are usually around 6, 12, or 18 ft. However, more often than not you’ll save money by buying a good quality by the roll.
**Rember this rule: never take chances with speaker wire length – don’t guess. Buy at least a little bit more than your estimate.
Copper-clad aluminum vs copper speaker wire
Copper-clad aluminum (CCA) wire has, in the last few years, become more and more common as the price of copper has gone up. It’s one of those “little things” you might not know when buying that companies aren’t telling you.
Unlike pure copper wire, copper-clad aluminum uses an aluminum wire core with a thin copper plating. From the outside, it misleadingly looks the same because of the plating.
Aluminum offers a lighter weight and lower cost than copper, so at first it may seem like a great way to replace the more expensive copper options. However, there’s a problem.
Aluminum has only 61% of the conductivity of copper (in other words, it has 39% more resistance) meaning it will take larger aluminum wires to get the same power handling, capacity, and resistance value.
Everyday use & what to know
In most cases like average listening & typical power levels, it’s not really a problem in day-to-day use. However, if you’re going to drive speakers at higher power levels or want the absolute best for your money, you’ll need to be sure to look for packaging that specifies the wire is 100% pure copper.
To get the same performance as true copper wire when buying CCA speaker wire, move up one gauge in size. For example, to replace 18 gauge copper wire, use a 16AWG or 14AWG CCA wire.
Hello, Marty. If one speaker is just over 50 feet from my receiver and the other only 22 feet, can I use different gauge wire, 14 for the 50 foot speaker and 16 for the 22 foot speaker, or should I use 14 gauge for both?
Hi Keith. Yes absolutely you can do that. It depends on the distance and power you expect to be using. If you use my calculator listed in the article it will recommend the correct wire gauge based on that for each length you need.
Best regards.
Use 14 gauge for both
This is excellent material for beginners.
I came here looking for some more advanced Info, Including component speaker system wire sizing, and a general overview of what precisely the component is doing. Does it provide most of the power through its dedicated power supply, which in turn would allow for a 24gauge signal wire from the Amp in the hope of saving space in my chasses as 6 wires to every set are going to become a massive nest of cables in my custom install.
Hi Joe. When you wrote “what precisely the component is doing. Does it provide most of the power through its dedicated power supply,[..]” I’m not clear on what you meant. Which component(s) specifically? You mentioned a component speaker system which doesn’t use a power supply but rather works from the existing amplifier speaker output(s). A passive (non-powered) speaker crossover works by reacting to the frequency and voltage present at the components, so no additional power is required.
I haven’t included 24AWG wire because it’s typically not commonly available for purchase, although perhaps I might extend my wire size calculator & the information here to provide it as well.
If you can tell me what the maximum RMS/continuous power you’ll be using is, the lengths of wire you need, and the type of component speaker system you have I can help more.
I have some additional articles here in case one of them is helpful to you: https://soundcertified.com/passive-audio-crossovers/
Best regards.
This was really great information not only did I get the answer I was looking for I learned a whole lot! Thx!
Awesome Jack, that’s great to hear! :)
Hi Marty
My car is a 2 seat sports MGF. I have just bought a Sony DSX-GS80 head unit with built in amp of 4x100w max power ( 45w rms ) with 2x Pioneer TS-A4670F 6X4 4 Ohm for the rear & 2 x Pioneer TS-A1670F 6.5″ 4 ohm for the doors.
I have a centre console front to rear so can get away with 2m run for each speaker. your calculator states 20AWG, is still the case or is it best to go for 18AWG or even 16AWG.
The car is a soft top so when its down the sound goes up, but is usually very up most of the time .
Sorry.
Also, is it possible to get ready made cables, rca to speaker lucas spade connectors at these lengths
Thank you
Hi Phil! Yes, you could definitely use 20AWG, although for practicality reasons, for car/boat/etc. installations I still usually use 18AWG as it’s 1) easier to find in many cases, 2) you can find it in bulk more easily, and 3) if you decide to upgrade later, having bigger gauge wire in place already avoids the need to change it out.
However, if you’ve got some decent 20AWG wire and the things I mentioned above don’t apply, it’s ok.
Regarding your second question. I don’t recall ever seeing a direct RCA to slide/spade connector ready-made wire cable. However, you can definitely get 1) RCA to wire terminal adapters (these are affordable, too!) or 2) RCA to bare wire cables. You could use either one of those and just extend the length a bit.
Personally I would go for option #1 because the 2nd one is usually a bit short, and the first one is a lot more flexible. All you’d need is some speaker wire and crimp connectors. I hope that helps!
Brilliant thanks Marty. Top job 👍
Eyyy Marty –
Upgrading all the interior speakers and amps in my SUV (22′ Subaru Ascent)
Running component 6×9’s rated at 145wrms & 6.5″ rated at 110wrms; front and rear respectively.
Amps will live under trunk floor compartment in rear of SUV.
Based on watage, will 14 guage be the best size for my application?
Lookling to rewire the entire vehicle when the install happens; buy once cry once mentality.
I don’t mind spending alittle to be happy :)
Hello JQ. There are two things to know here:
1. The length of wire you’ll be using (16 to 18ft from the trunk is pretty typical).
2. The amplifier’s maximum rated continuous/RMS power output (which you didn’t mention).
However, it’s pretty likely it’ll end up around 14AWG and if you’re not running the speakers at full power that should be fine. For average listening, a good 18AWG wire would be fine as well, but yes I definitely agree about planning ahead when installing and do the same myself.
I’d use a reasonably priced 14AWG wire of adequate quality. Best regards!
Oops, lol
“amplifier’s maximum rated continuous/RMS power output” is 220xw@4ohms in bridged mode.
Running it this way to provide more power w/o pushing the amps too hard. Running 2 amps, one for the fronts and one for the rears. Thanks again!
Hi, useful article thanks.
I’m curious about your statement that solid core cable is terrible for audio? I’ve used it myself in the past and found it to perform very well for audio applications. Is it just the lack of flexibility that makes you recommend against it?
Ta
Hi there. I didn’t intend to mean that it’s not good in terms of sound quality but yes the issues that come with solid core wire like how it doesn’t handle vibration well or is very difficult for vehicle installations.
I can see how I need to clarify that so I’ll update the article to better explain. Thanks for bringing it up!
Hello,
I’m looking to run some speaker wire from my Yamaha receiver (100 watts per channel) to my Klipsch surround speakers in my living room. I plan to route the wire inside the baseboard trim, the first run of wire will be approximately 25 feet and the second approximately 35 feet. Will 18 gauge in-wall stranded wire work alright? I want the smallest wire possible as it’s going to be concealed. Thanks!
Chris
Hi Chris. Yes, 18AWG copper or 16AWG CCA wire will work for that, assuming they’re 8Ω speakers. If you need to you can use my calculator here: https://soundcertified.com/speaker-wire-gauge-calculator/#SPEAKER_WIRE_GAUGE_CALCULATOR
Best regards.