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Foam cannons and foam guns are highly popular devices, typically used for cleaning cars. They make cleaning efficient, convenient and fun. However, there’s some confusion regarding the difference between these two types of devices.
The foam cannon vs. foam gun comparison is easy to explain but it still leaves a bit of room for case-by-case variations and personal preferences. That’s because, as with most other appliances, there are many different models and brands for each type of device. With the change of quality can come a lot of variations in the foam and the overall cleaning results.
In this guide, we’ll cover what foam cannons and foam guns are, highlighting their pros and cons and which to choose.
What Is A Foam Cannon – A Quick Definition

Twinkle Star Foam Cannon in action. Check price here.
Foam cannons are attachments for pressure washers that are sold separately to them. The reason being that foam cannons are quite specialized and not everyone who wants a pressure washer needs a foam cannon.
The purpose of a foam cannon is to use the high-pressure water jets generated by the pressure washer and combine them with a soap mixture and a foaming nozzle to create nice and thick foam for washing, usually used on vehicles.
The way the foam cannon works is by simply releasing soap into the water stream and turning it into foam through the foaming nozzle. Foam cannons achieve that relatively simple purpose with their equally simple design.

The standard foam cannon is made out of the following components:
- A cylindrical water container where you can mix warm/hot water and soap. The exact ratio of the mixture will depend on the type of soap you’re using so follow its instructions. The more soap you put in the mixture, the thicker the foam is going to be. Also, make sure you use specialized soap for vehicle foam washing as they are designed for maximum foam and for the best possible cleaning.
Another important feature of the water canister is that it can regulate the amount of soap it releases into the high-pressure water stream. For more foam, you’ll want to set it at max but you can also set it to release less soap if you don’t need to use that much foam. A good pressure washer with a nice soap will generate great thick foam suds.
- A foaming nozzle that can be rotated for multiple different spraying patterns. That nozzle may be similar to some of the nozzle attachments of your pressure washer but it should be generally better if you’ve got a nice foam cannon.
- A socket for a pressure washer wand located on the opposite side of the foaming nozzle. This is where the high-pressure water will come from before it’s mixed with the soap from the canister.
- There will also usually be a filter between the nozzle and the canister to filter debris from the soap so that they don’t scratch your vehicle.
How To Use A Foam Cannon
Foam cannons are fairly easy to use and can be interesting and fun when done right:
- Once you’ve set everything up you only have to turn on the water and start spraying your vehicle. The two most preferred nozzle settings are vertical and horizontal spraying. Both will cover your car, truck, or other vehicles from top to bottom, so just pick your preferred setting. How much foam you’re going to have to use will depend on the thickness of the foam and the type of soap you’re using. The stronger the soap is, the more effective it’s going to be but it will also start drying sooner. Another reason to be careful how much soap you’re using is that too much soap can clog the nozzle and its filter. Not to mention that using too much soap needlessly is simply a waste.
- Once you’ve covered your vehicle with thick foam, the next step is to just do nothing for a couple of minutes. Don’t rinse off the foam, let it sit there for a while and get absorbed into the dirt and dust on your vehicle. Even the thickest foam will slowly start falling to the ground, gently dragging most of the dirt with it.
- Don’t wait too long, however – the foam will start drying after a while which is a No-No – you want to rinse it off after it has absorbed into the dirt and started dragging it off your car’s surface but before it has dried off.
- Proceed to hand-washing your car for specific spots with a sponge if and where you need to. Even the best foam cannon won’t usually be enough to fully clean your car. You’ll still likely want to scrub some spots with a sponge. However, a good foam cannon will remove the majority of the dirt on its own, reducing most of the handwashing you’ll need to do afterward. What’s even more important, however, is that foam cannons will reduce scratches and swirl marks while washing because there’ll be much less dust and dirt in the soap when hand-scrubbing your vehicle.
Foam Cannon Prices
Depending on their brand and quality, foam cannons can range in price, starting at around $20. You’d rarely find a foam cannon with a 3-digit price tag and it’s debatable whether it will be worth it.
At the end of the day, foam cannons are great tools for washing your car but they are also fairly simple so overinflated prices are usually unjustified unless the foam canon comes with a lot of extra features and attachments.
The pressure washer is the more expensive tool in a foam cannon + pressure washer combination as pressure washers will usually range between $100 and several hundred dollars. So, while getting a foam cannon for your pressure washer to help wash your vehicles is a good idea, getting a pressure washer just for that is usually going to be a waste. Fortunately, pressure washers have many more uses and applications which make them an excellent tool to have around the house.
What Is A Foam Gun – A Quick Definition
Foam guns are a similar and simpler version of foam cannons which is why the two are often confused with each other. If you go and search for either foam gun or foam cannon on sites like Amazon and Aliexpress, you’ll be greeted by dozens of items with names like:
- foam gun
- sprinkle snow foam blaster
- cross nozzle foam cannon
- jet wash release
as if it’s all the same.
While similar to foam cannons, foam guns do have one major difference – they have a “gun handle” attachment that can be connected to a garden hose but not a pressure washer. That handle is essentially designed to act as the pressure washer’s wand.

The Evilto garden hose nozzle in action. Check price here.
This is a pretty big difference because foam guns can only use garden hoses which offer much lower water pressure than the thousands of PSI (pounds per square inch) that pressure washers can offer.
Aside from that, foam guns have a very similar build to foam cannons. They have nearly identical water and soap canisters and similar foaming nozzles. The canister can regulate how much soap is released into the water stream and there’s usually a filter before the nozzle to stop the bigger soap particles. The only difference is the small “gun handle” attachment which connects to the water canister and the garden hose.
How To Use A Foam Gun
The way you use a foam gun is also very similar to how you use foam cannons.
- First, you’ll have to attach the device to the water source, and then fill the canister with warm water and an appropriate car wash soap. Once done, start spraying.
- As with foam cannons, leave the foam on the car for a couple of minutes (again – depending on how thick the foam suds are) before your rinse it off.
- The main difference here is that you usually won’t have to wait too long to rinse the foam because it usually won’t be as thick as the foam from a foam cannon and it will drip to the ground pretty quickly. The concentration of the soap and the pressure generated from your garden hose will affect the thickness of the foam, of course, as will the quality of the foam gun.
There are some good foam guns out there that can generate excellent foam with the right garden hose and soap. Generally, however, foam guns don’t produce as thick foam suds as most foam cannons.
Foam gun Prices
Despite foam guns being technically “inferior” to foam cannons, they are similarly priced. That’s because both devices are very similar in their construction so their production costs are similar too. That’s why you’ll often find foam guns starting at $20 but not going much higher than that.
What Is A “Foam Blaster”?
As you keep browsing sites for foam cannons and foam guns you’ll inevitably see items called “foam blasters”.
Just so you don’t wonder why we haven’t mentioned them, it’s because they are a loose term that’s usually used for foam guns but can sometimes be slapped on a foam cannon as well.
Simply put, foam blasters are not a thing and many sellers only use that term because it “sounds cool”.
Pros And Cons Of Foam Cannons And Foam Guns – How They Compare

With all that out of the way, the pros and cons of foam cannons and foam guns are fairly self-evident. Still, let’s break them down quickly here:
Pros Of Foam Cannons:
- Excellent foam thanks to the high water pressure generated from the pressure washer.
- Very water-efficient and soap-efficient since the water pressure helps maximize the foam’s thickness with no need for excess water consumption.
- Slightly simpler construction as foam cannons don’t have a “gun handle” and the pressure washer wands connect directly into the neck of the water canister.
- Very affordable price and a great purchase if you already have a pressure washer.
Cons Of Foam Cannons:
- You need to have a pressure washer to use a foam cannon. If you don’t, you’ll have to buy one and they are anything but cheap. If you don’t have any other uses for a pressure washer other than to foam your car, the hundreds of dollars price tag on most pressure washers is usually not worth it for most people. Using a friend’s or a neighbor’s pressure washer is a good solution here but you’ll be dependant on them which many people don’t like.
Pros Of Foam Guns:
- Foam guns don’t require pressure washers to work and can be used with a simple garden hose.
- They come at the same affordable price and have a similarly simple and straightforward construction as foam cannons.
- The lack of a pressure washer makes them even easier to use.
Cons of foam guns:
- On average, foam guns don’t generate as good/thick foam as foam cannons. Again, this will depend on the particular models of foam guns and foam cannons + pressure washer you choose to compare but the average comparison usually goes in favor of foam cannons.
- The effectiveness of the foam gun is reliant on the water pressure coming out of the garden hose. If you have lower water pressure in your home, the foam gun will be even less effective.
- The reduced effectiveness of foam guns usually leads many homeowners to eventually purchase a foam cannon and a pressure washer anyway which turns foam guns into a waste of money.
Which Is Right For You?
The straight-forward answer here is that you should get a foam cannon if you have a pressure washer and a foam gun if you don’t. In either case, you should make sure you get a high-quality product as wasting money on something that won’t work well enough is not fun.
Still, an extra consideration here is that you might want to buy a pressure washer if you don’t have one. Granted, getting a pressure washer just for foaming your car is not a well-justified expense, however, pressure washers have much more uses than just car-washing.