Choosing the best Kärcher to buy for car cleaning can be a difficult task as there are so many different models in the range to navigate.
In this article, I’ll break down what you actually need to wash your car and the specifications to look for, then explain the Kärcher line-up and give my recommendation as to which is the most suitable based on your budget.
The Quick Answer
The Kärcher K4 Full Control Pressure Washer is a great all round option to clean a car. It has more power and a higher flow rate than a K2 and K3 but is not much more expensive. It is significantly cheaper than the K5 and K7 models which have unnecessary features for car cleaning.
What You Need from a Pressure Washer
To choose which Kärcher model in the range is most suitable, you need to know what features and specifications are suitable for car cleaning. Here ar the two main specs to consider:
- Pressure: 110-150 Bar is best
- Flow Rate: 350-500 litres/ hour (LPM) is best
A jet washer with a pressure of much lower than 110 Bar is usually not strong enough to remove dirt effectively from the vehicle. You don’t want to go too high though as it can be damaging to the paintwork.
There are other factors you can consider as well:
- Weight and shape
- Hose length
- Cable length
- Controls and ease if use
- Extras and accessories
Kärcher Models Explained
There are several different ranges in the Kärcher lineup, which can make things a bit confusing.
Here’s a list of the ranges that the Kärcher models can be categorised into:
- K2
- K3
- K4
- K5
- K7
The higher the number, the more powerful (and more expensive), the pressure washer is.
The models get a bit complicated from here on out, because there are different variants of the K4 for example.
So it’s best to choose which number you want first before moving on. The number will determine the specification of the pressure washer. Here’s what they all mean.
| K Series | Max Pressure (Bar) | Max Flow Rate (LPH) |
| K2 | 110 | 360 |
| K3 | 120 | 380 |
| K4 | 130 | 420 |
| K5 | 145 | 500 |
| K7 | 180 | 550 |
All the Kärcher range will be sufficient to clean a car. However, the most suitable models are the K3, K4, K5 K7.
The K2 is on the weaker side so may not be enough for heavily soiled vehicles. The K7 is more than good enough to clean a car with, but the extra pressure and higher flow rate isn’t necessary so may not be very cost effective if you only intend to clean the car with it.
Kärcher K2
This is the cheapest Kärcher model available starting at around $100 or £80. The max pressure is 110 Bar and the max flow rate is 360 LPM. The pressure is generally good enough for cleaning most cars making it a good budget option, however it is on the low end of the range.
Here are the K2 models available going from cheapest to most expensive:
| K2 Model | Weight (kg) | Dimensions L x W x H (mm) | Extras |
| K2 Compact | 3.7 | 180 x 219 x 389 | None |
| K2 Compact Home | 3.7 | 180 x 219 x 389 | Patio cleaner and detergent |
| K2 Full Control | 4.3 | 246 x 280 x 586 | None |
| K2 Full Control Home | 4.3 | 246 x 280 x 586 | Patio cleaner and detergent |
Check out my comparison between the Karcher K2 and K3 for more information.
Kärcher K3
There is just one model on the K3 range at the moment on the official website, the K3 Home. Here are the specs:
- Max pressure: 120 bar
- Max flow rate: 380 LPH
- Weight: 6.5 kg
- Dimensions L x W x H (mm): 275 x 279 x 802
- Extras: patio cleaner and detergent
This makes it around 1.5 times heavier than the K2 range, but it is still quite compact and lightweight enough to carry around easily. It’s a good option for car cleaning as it’s a bit cheaper than the K4, but more powerful than the entry level K2.
The only real weakness, is that it has quite a modest flow rate, but for most this will not be noticeable.
Check out my comparison between the Karcher K3 and K4 for more information.
Kärcher K4
The K4 is probably the most popular option and the one that I personally own. It’s more than powerful enough for cleaning cars. It has a max pressure of 130 bar and a max flow rate of 420 LPH. This gives it enough pressure for other applications like cleaning fences and flagstones.
Here is a comparison of the K4 models available ranging from least to most expensive.
| K4 Model | Weight (kg) | Dimensions L x W x H (mm) | Extras |
| K4 Compact | 11 | 348 x 308 x 520 | None |
| K4 Full Control | 11.4 | 397 x 305 x 584 | None |
| K4 Full Control Home | 11.4 | 397 x 305 x 584 | Patio cleaner and detergent |
| K4 Premium Full Control Car and Home | 12 | 411 x 305 x 584 | Multi-jet lance, patio cleaner, rotating wash brush, foam nozzle, detergent, car shampoo |
The K4 Full Control and K4 Compact options are probably the best value for money if you are just cleaning cars.
The rotating wash brush in the premium version is likely to cause minor paintwork scratches, and better quality foam lances can be purchased from aftermarket suppliers. The multi-jet lance is useful and avoids having to keep switching attachments however it is quite an expensive upgrade.
Check out my comparison between the Karcher K4 and Karcher K2 if you’re torn between these two pressure washers.
Kärcher K5
The Kärcher K5 series is more than powerful enough to clean a car. It has a max pressure of 145 bar and max flow rate of 500 LPH. This makes it suitable for cleaning stonewalls and garden paths. It is more expensive than the K4, so not worth the upgrade unless you intend to use it for other things as well.
Here is a comparison of the models in the K5 range, going from least to most expensive:
| K5 Model | Weight (kg) | Dimensions L x W x H (mm) | Extras |
| K5 Compact | 12 | 354 x 308 x 520 | None |
| K5 Full Control | 12 | 354 x 308 x 520 | Patio cleaner, detergent |
| K5 Full Control Plus | 13.6 | 411 x 305 x 584 | Multi-jet lance |
| K5 Premium Full Control Plus Home | 12.7 | 397 x 305 x 584 | Multi-jet lance, patio cleaner, detergent |
Check out my comparison between the Karcher K4 and Karcher K5 for more detail about each model.
Kärcher K7
The most powerful, and most expensive Kärcher model is the K7. It boasts a max pressure of 180 bar and max flow rate of 550 LPH. This makes it more than powerful enough to clean a car, and allows it to tackle patios, stonewalls and other areas in the garden.
Here is a comparison between the two types of K7, the compact, and full control models.
| K5 Model | Weight (kg) | Dimensions L x W x H (mm) | Extras |
| K7 Compact | 15.8 | 378 x 291 x 516 | None |
| K7 Premium Full Control Plus Home | 12 | 354 x 308 x 520 | Multi-jet lance, patio cleaner, detergent |
Check out my comparison between the Karcher K5 and K7.
Compact vs Full Control
Most Karcher models either come as a full control variant or compact variant. So for example, you can get a K4 Compact, and a K4 Full Control.
There is no difference in pressure or flow rate between Karcher Compact and Full Control models.
Here are the differences:
- Compact models are cheaper, smaller and lighter
- Full control models have a built in detergent bottle
- Full control models have a hose reel and wheels
- Full control models have a trigger with visual controls, whereas compact models are only controlled from the machine itself, not the trigger
The compact series is cheaper, smaller, lighter however has a smaller lance without visual controls and the detergent bottle isn’t built in like it is with the full control model. Full control models have a hose reel and wheels unlike compact models.
Premium, Plus, Car and Home Variants Explained
Within the compact and full control ranges, there are some more variants, such as “plus” and “home”. So for example, you can purchase a K5 Full Control Plus, or just a a K5 Full Control. Here’s what the difference is.
- Plus: multi-jet lance so you don’t need to change attachments. Also a built-in detergent application function.
- Home: includes extras such as a patio cleaner and detergent
- Car: includes extras such as a rotating wash brush, foam nozzle and car shampoo
Best Option
The Kärcher K4 Full Control Pressure Washer is one of the most popular options for cleaning cars. It couples good value for money, with premium features making it a cost-effective option. Here are the specifications.
| Specification | Description |
| Max pressure (bar) | 130 |
| Flow rate (LPH) | 420 |
| Power rating (kW) | 1.8 |
| Weight (kg) | 11.4 |
| Dimensions L X W X H (mm) | 397 x 305 x 584 |
| Hose length | 6m |
Here is a list of some of the stand out features.
| Feature | Description |
| Trigger | Full control trigger has built-in controls to make adjustments without touching the pressure washer itself |
| Storage | Has a parking position to store the trigger and a hose reel |
| Plug and clean | Allows application of detergents directly through the pressure washer |
| Portable | Telescopic handle and wheels |
Cleaning Your Car with a Kärcher
Cleaning your car with a Karcher is very easy. The controls are all simple to operate, and you can get a range of extras to make the task even easier.
Karcher have their own range of accessories designed to help clean a car including their own brand foam cannon, shampoo, and brush. However, the quality of aftermarket accessories, from my experience is much better and offers you more value for money.
You can check out my recommended accessories here.
Thanks for reading! I hope you’ve found this article helpful. Don’t forget to check out the rest of the website to learn everything you need to know about cleaning your car.