Kärcher K4 vs K5 for Car Washing: Which to Buy? (2026)
Last updated 21 October 2026. Prices and ratings checked on Amazon UK that day.
For washing a car, the K4 is the better-value pick on price and the K5 is worth considering if you want its 10m hose, higher listed flow or built-in hose reel. On Amazon UK the K5 lists 145 bar and 500 l/h against 130 bar and 420 l/h for the K4, but neither number tells you how gently a machine treats paint. What matters more for cars is whether the box includes a foam jet, wash brush and car shampoo (the “Car & Home” versions do) and whether you can adjust the pressure (Power Control). We compared seven K4 and K5 variants from £155.94 to £420.00 on 21 October 2026.
Quick verdict: choose the K4 if you want to spend less: the K4 Power Control Flex (£188.00, 4.6 from 378 ratings) for adjustable pressure and an 8m hose, or the K4 WCM Flex Car & Home (£269.00) for the car kit in the box. Choose the K5 if you want the longer hose or a reel: the K5 WCM Flex Car & Home (£302.77) with the car kit and a 10m hose, or the K5 Comfort Premium (£289.00) with an integrated hose reel. The K5 Power Control Flex Car & Home is listed at £420.00 by a third-party seller while the newer K5 WCM Flex is listed lower. The K4 is cheaper for the same kit; that is a price difference, not a listed performance difference. Listings quote weights and warranties inconsistently, and pressures in different units, and this guide flags where they do.
Jump to: Quick picks · Specs side by side · Buying guide · How we compiled this shortlist · FAQs · Which to buy
Quick picks: Kärcher K4 vs K5 for car washing
These labels describe what each machine is listed with. See how we compiled this shortlist for the method.
- Lowest price here (K4): Kärcher K 4 Classic (£155.94)
- K4 with Power Control and an 8m hose: Kärcher K 4 Power Control Flex (£188.00)
- Lowest-priced K5 here, but a home kit: Kärcher K 5 Classic Home (£249.99)
- K4 here with the car kit and eco!Booster: Kärcher K 4 WCM Flex Car & Home (£269.00)
- K5 with an integrated hose reel (10m hose), listed with eco!Booster: Kärcher K 5 Comfort Premium (£289.00)
- K5 with the car kit and eco!Booster: Kärcher K 5 WCM Flex Car & Home (£302.77)
- K5 with Power Control and the car kit (third-party seller price): Kärcher K 5 Power Control Flex Car & Home (£420.00)
Kärcher K4 vs K5 specs side by side
| K4 (three models here) | K5 (four models here) | |
|---|---|---|
| Maximum pressure | 130 bar (about 1,885 psi, converted) | 145 bar (about 2,103 psi, converted) |
| Flow rate | 420 l/h (7 l/min) | 500 l/h (about 8.3 l/min) |
| Area coverage | 30 m²/h | 40 m²/h |
| Hose | 6m (Classic), 8m (others) | 8m (Classic Home), 10m (others) |
| Integrated hose reel | None listed | Comfort Premium |
| Price range here | £155.94 to £269.00 | £249.99 to £420.00 |
| Car kit versions here | WCM Flex Car & Home (£269.00) | WCM Flex Car & Home (£302.77), Power Control Flex Car & Home (£420.00) |
The table below lists each of the seven models.
| Model | Price (21 Oct 2026) | Amazon rating (number of ratings) | Listed pressure and flow | Listed hose | Car kit listed in the box | Listed warranty or guarantee |
|---|---|---|---|---|---|---|
| K 4 Classic | £155.94 | 4.4 (409) | 130 bar, 420 l/h | 6m | No (spray lance, Dirt Blaster) | Not stated |
| K 4 Power Control Flex | £188.00 | 4.6 (378) | 130 bar, 420 l/h | 8m (PremiumFlex) | No (Dirt Blaster, spray lance) | 2-year warranty (spec); 5 years with registration (page text) |
| K 5 Classic Home | £249.99 | 4.6 (166) | 145 bar, 500 l/h | 8m | No (Home kit: T 5 surface cleaner, stone & façade cleaner) | 2-year warranty |
| K 4 WCM Flex Car & Home | £269.00 | 4.3 (47) | 130 bar, 420 l/h | 8m PremiumFlex | Yes (wash brush, foam jet, car shampoo) | Listed as a 5-year guarantee (check registration conditions) |
| K 5 Comfort Premium | £289.00 | 4.2 (30) | 145 bar, 500 l/h | 10m, with hose reel | Holder for a 2-in-1 cleaning agent system with foam nozzle; not clearly listed in the box | Not stated |
| K 5 WCM Flex Car & Home | £302.77 | 4.6 (36) | 145 bar, 500 l/h | 10m PremiumFlex | Yes (wash brush, foam jet, car shampoo) | Listed as a 5-year guarantee (check registration conditions) |
| K 5 Power Control Flex Car & Home | £420.00 | 4.5 (121) | 145 bar, 500 l/h | 10m (PremiumFlex) | Yes (foam jet, rotating wash brush, 1L car shampoo) | 5 years with registration (page text) |
Pressures, flow rates, hose lengths, kits and warranties are manufacturer claims taken from each Amazon UK listing. Several listings quote different weights in the title, the highlights and the specification table, so weights are left out of this table; see below. The K4 and K5 “Car & Home” models with fewer than 50 ratings (K4 WCM, K5 Comfort Premium, K5 WCM) have small rating samples.
How to choose: Kärcher K4 vs K5 for washing a car
What is the difference between the Kärcher K4 and K5?
On the listings here, the K4 models are rated at a maximum of 130 bar and 420 litres an hour, and the K5 models at 145 bar and 500 litres an hour. The listings give an area coverage of 30 m² an hour for the K4 and 40 m² an hour for the K5. Hose lengths run from 6m on the K4 Classic to 10m on the K5 models. The area figures are patio-cleaning figures: for a car, pressure and flow tell you how quickly the machine can work, not how gently it will treat paint.
Is more pressure better for washing a car?
Not necessarily. The listings here give maximum pressures and none gives a safe pressure for car paint, so follow the manufacturer’s instructions. Kärcher’s text for the eco!Booster lance on the K4 WCM Flex and K5 WCM Flex Car & Home models describes it as perfect for sensitive surfaces such as wooden decks or cars, and the K4 Power Control Flex describes adjusting the pressure to suit each surface, with a Power Control gun that shows the pressure level. For car washing, the features that matter are an adjustable pressure setting, a foam jet or snow foam lance and a hose long enough to reach the whole car.
Do the K4 and K5 come with a snow foam lance?
Only some of them, and none of the listings calls it a snow foam lance. The three “Car & Home” models list a foam jet and a wash brush with car shampoo. The K5 Comfort Premium shows a holder for a 2-in-1 cleaning agent system with a foam nozzle but does not clearly list one in the box. The Classic and Power Control Flex K4 listings do not list a foam jet in the box, and Amazon suggests a Kärcher FJ6 foam jet nozzle (0.6 litre) as an add-on. Third-party foam lances for the K2 to K7 range are also sold on Amazon UK, but check they fit your model.
Which hose is best for car washing?
A longer hose helps you walk round a car. The listings give 6m (K4 Classic), 8m (K4 Power Control Flex, K4 WCM and K5 Classic Home) and 10m (K5 WCM, K5 Power Control Flex and K5 Comfort Premium). The K4 WCM, K5 WCM and Power Control Flex pages mention an anti-twist “PremiumFlex” hose, and the K5 Comfort Premium lists an integrated hose reel that winds the 10m hose. Third-party replacement hoses for the K2 to K7 range appear on the Amazon pages; check compatibility with your model before you buy.
Listed weights do not agree
Most listings give two different weights, one in the title or highlights and another in the specification table (for example 11.5kg against 6.3kg on the K4 Power Control Flex, and 13kg against 18.37kg on the K5 Power Control Flex). Treat weights as uncertain and check the manufacturer’s page if lifting or storage matters to you.
Safety
Follow the manufacturer’s instructions for your machine. Wear eye protection, never point the jet at people or animals, and keep a sensible distance from paint, trim and tyres. Check that your machine is connected to a suitable water supply and an outdoor-safe power supply, and ask a qualified electrician if you are unsure about the supply.
Kärcher K 4 Classic: the lowest price here
Price: £155.94 | Amazon rating: 4.4 from 409 ratings
The K4 Classic is the cheapest machine here. The listing describes 130 bar and 420 litres an hour, a 6m hose, a trigger gun, a Dirt Blaster nozzle and a spray lance, and says it is suitable for patios, driveways, cars and garden furniture. It lists no foam jet or car kit, though the page shows a Kärcher FJ6 foam jet nozzle as a separate add-on. The listing gives 5.68kg in the specification table and 4.6kg elsewhere, and no warranty length.
Check the Kärcher K 4 Classic on Amazon UK
Kärcher K 4 Power Control Flex: 8m hose and adjustable pressure
Price: £188.00 | Amazon rating: 4.6 from 378 ratings
The K4 Power Control Flex is the best-rated K4 here with a large number of ratings. The listing describes 130 bar and 420 litres an hour, an 8m hose, a water filter, a Dirt Blaster nozzle, a spray lance, and Power Control technology that lets you adjust the pressure to suit each surface; the page says the pressure level is adjusted at the lance and shown on the gun. The specification table gives a two-year manufacturer warranty, while the page text says five years with registration within 28 days. The title says 11.5kg and the specification table says 6.3kg. It does not list a foam jet in the box.
Check the Kärcher K 4 Power Control Flex on Amazon UK
Kärcher K 5 Classic Home: the lowest-priced K5 here
Price: £249.99 | Amazon rating: 4.6 from 166 ratings
The K5 Classic Home is the lowest-priced K5 in this shortlist, but it is a home kit rather than a car kit (Kärcher’s comparison table on the page also shows a K 5 Classic that is not in this shortlist). The listing describes 145 bar, 500 litres an hour, an 8m hose, a high-pressure gun, a Dirt Blaster, a spray lance, a T 5 surface cleaner and 1 litre of stone and façade cleaner, with a two-year manufacturer warranty. It does not list a foam jet or car shampoo. The highlights say 5.6kg while the specification table says 9.77kg.
Check the Kärcher K 5 Classic Home on Amazon UK
Kärcher K 4 WCM Flex Car & Home: the K4 with a car kit
Price: £269.00 | Amazon rating: 4.3 from 47 ratings (small sample)
The K4 WCM Flex is the K4 in this shortlist with the full car kit. The listing describes 130 bar, 420 litres an hour, an 8m PremiumFlex anti-twist hose, an eco!Booster lance, a car accessory kit with a wash brush, foam jet and natural car shampoo, a T 5 patio cleaner with stone and façade detergent, on-board storage for the lances, cable and hose, and a five-year guarantee (check the registration conditions). It lists an 11.82kg weight. The rating rests on 47 ratings.
Check the Kärcher K 4 WCM Flex Car & Home on Amazon UK
Kärcher K 5 Comfort Premium: integrated hose reel
Price: £289.00 | Amazon rating: 4.2 from 30 ratings (small sample)
The Comfort Premium is the K5 with a built-in hose reel. The listing describes 145 bar, 500 litres an hour, a 10m high-pressure hose wound by an integrated reel, an “eco!Booster” mention in its title, wheels with a lockable telescopic handle, and holders for the gun, hose, cable and a 2-in-1 cleaning agent system including a foam nozzle (the listing does not clearly say a foam nozzle is in the box). It has the lowest rating here (4.2) on 30 ratings, and the highlights say 19.2kg while the specification table says 13.8kg.
Check the Kärcher K 5 Comfort Premium on Amazon UK
Kärcher K 5 WCM Flex Car & Home: the K5 with a car kit
Price: £302.77 | Amazon rating: 4.6 from 36 ratings (small sample)
The K5 WCM Flex is the lower-priced of the two K5 models here with the car kit and a long hose. The listing describes 145 bar, 500 litres an hour, a 10m PremiumFlex anti-twist hose, an eco!Booster lance, a car accessory kit with a wash brush, foam jet and natural car shampoo, a T 5 patio cleaner, on-board storage and a five-year guarantee (check the registration conditions). The highlights say 18.7kg while the specification table says 12.55kg. The rating rests on 36 ratings.
Check the Kärcher K 5 WCM Flex Car & Home on Amazon UK
Kärcher K 5 Power Control Flex Car & Home: the most expensive
Price: £420.00 | Amazon rating: 4.5 from 121 ratings
This is the most expensive machine here. The listing describes 145 bar, 500 litres an hour, a 10m hose, a water filter, a foam jet, a rotating wash brush, 1 litre of car shampoo and a patio kit, with a five-year guarantee on registration within 28 days (two years as standard). It is a third-party seller price on 21 October 2026. The title says “Home Kit” but the page text lists the car kit. The title says 13kg and the specification table says 18.37kg. The page also points to a newer model, the K5 WCM Flex above, at a lower price, so check which version you are buying.
Check the Kärcher K 5 Power Control Flex on Amazon UK
How we compiled this shortlist
This is a research-based shortlist. Everything above comes from Amazon UK listings and manufacturer claims on those pages, checked on 21 October 2026, apart from the general buying and safety advice. Kärcher and the model names are used descriptively.
We started with Amazon UK, where most British buyers will shop, and looked at Kärcher K4 and K5 pressure washers listed on Amazon UK. We left out the K2, K3 and K7 ranges, accessories and third-party foam lances, and the “Home” versions of the K4 Classic and K4 WCM, which duplicate the models above without the car kit. We compared each listing’s stated specifications, the manufacturer’s own claims on that page, and the customer rating and number of ratings shown at the time. The shortlist covers three K4 and four K5 variants and does not include every version of either model; Kärcher’s comparison tables on the pages also show other versions, such as a K 4 Power Control Flex Car & Home and a K 5 Classic.
Ratings move over time, and the number of ratings matters: the K4 Classic (409) and K4 Power Control Flex (378) have the most, while the K5 Comfort Premium (30) has the fewest. Prices were accurate on 21 October 2026 and change frequently, so use the links to see the current price. We will update this guide when prices, ratings or availability change.
Kärcher K4 vs K5 FAQs
Is the Kärcher K5 better than the K4 for washing a car?
Not by much for car washing. The K5 lists 145 bar and 500 l/h against 130 bar and 420 l/h for the K4, plus longer hoses, but the car kit and adjustable pressure matter more than the model number. Compare what is in the box before you decide.
How long is the hose on the K4 and K5?
The K4 Classic lists 6m and the other K4 models 8m. The K5 Classic Home lists 8m and the other K5 models 10m. Only the K5 Comfort Premium lists an integrated hose reel.
What is the difference between the K4 Classic and the K4 Power Control Flex?
The Power Control Flex (£188.00) lists an 8m hose and adjustable pressure with the level shown on the gun, while the Classic (£155.94) lists a 6m hose and no pressure adjustment.
Which Kärcher is best for washing a car?
Of the seven models compared on 21 October 2026, the “Car & Home” versions list a foam jet, a wash brush and car shampoo: the K4 WCM Flex (£269.00), the K5 WCM Flex (£302.77) and the K5 Power Control Flex (£420.00).
Can you use a snow foam lance on a Kärcher K4 or K5?
Kärcher sells a Foam Jet nozzle for its pressure washers, and several third-party snow foam lances for the K2 to K7 range appear on Amazon UK. Check that the fitting matches your model before you buy.
Which Kärcher should you buy for washing a car?
If you want the lowest price, start with the K 4 Classic and add a foam jet separately. The K 4 Power Control Flex adds an adjustable pressure setting and an 8m hose, and the K 4 WCM Flex Car & Home gives you the car kit. If you want the K5’s higher listed flow and a 10m hose, the K 5 WCM Flex Car & Home includes the car kit at a lower price than the K 5 Power Control Flex, the K 5 Comfort Premium adds a hose reel, and the K 5 Power Control Flex is the most expensive. Check the kit, hose length, warranty and weight on the product page before you order.
Affiliate disclosure: The Motoring World may earn a commission if you buy through links to Amazon UK, at no extra cost to you. We link to Amazon UK because most readers shop there; prices may differ elsewhere.
Prices, ratings and specifications were taken from Amazon UK listings on 21 October 2026 and may have changed.
