The 10 Best Offers for 4000w Generator - December 2025

Last updated: 13. December 2025
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1
Best Choice
9.9
Oxseryn

  • Capture: 4000 Max Watts, 3200 Running Watts, Gas Powered by 208CC 4-Stroke OHV Engine, Perfect for Home Emergency Use and RV Camping.
  • Up to 14 hours run time per tank, 2 gallon fuel tank with fuel gauge.
  • MASK - Includes 1 x 12V DC port, 2 x 120V AC ports, 1 x 30A RV port, versatile ports meet all your needs.
  • 72dBA from 23ft away, undisturbed camping or home use.
  • Compact design makes it easy to carry.
  • All generators are functionally tested in the factory, so there may be a slight gas smell when you receive it.
Colour Manufacturer Weight
Orange + Black Oxseryn 25.4 kg
£82546
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2
Best Value
9.8
maXpeedingrods
Save £68.99 Today!
£288.99 (24% OFF!)

Free Delivery**
  • 【Multifunction Power Supplier】4-stroke petrol generator produces 3500W max watts and 3200W running watts. It is easily able to keep the lighting system or a small family house, power air conditioners and many other small appliances such as refrigerators,coffee machine at the same time.
  • 【Provide Clean Power】This inverter technology provides more steady power, produces clean power to safely operate and prevent damage to sensitive electronics such as phones, tablets, televisions and computers.
  • 【Multi-Function Display】Easy to monitor voltage and frequency power; display remaining fuel, which is suitable for timely fuel change; display cumulative runtime, which is suitable for later generator maintenance; display unique runtime, perfect timer function.
  • 【Lightweight and Powerful Motor】Only 26 kg, small and compact, easy to carry, 223 cc OHV motor with two 230 V ports and a 12 V DC connector, provides plenty of power for multiple tasks.
  • 【Brand Warranty】 Maxpeedingrods warrants all the inverter generators against defects in workmanship under normal use for a period of 2 years from the date of retail purchase by the original end-user purchaser ("Warranty Period"), and free lifetime technical support and customer service.
Colour Manufacturer Weight
Orange/Black maXpeedingrods 26 kg
£22000
Was: £288.99 -24%
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3
9.8
United Power Equipment Co.,Ltd
Save £57.00 Today!
£379.99 (15% OFF!)

Free Delivery**
  • 223cc 4-stroke OHV engine produces 3800 peak watts and 3500 rated watts with recoil start for up to 10 hours at quarter-load on 10 L, 50Hz
  • Intelligent gauge keeps track of voltage ,run-time and hertz and track power output, plus feature low oil led and economic mode to save fuel
  • Includes two 230V AC outlets, one 12V DC 8.3A outlet and two 5V USB ports; Parallel ready to connect 2 generators for twice the power (parallel kit sold separately)
  • This portable generator for camping produces the clean power required by a variety of sensitive electronics such as phones, TV
  • All generators are functionally tested in the factory to guarantee quality with CE EURO-V compliant; Backed by a 1 year limited warranty with lifetime technical guidance from experts
Colour Manufacturer Weight
Yellow and Black Aceup Energy 28 kg
£32299
RRP: £379.99 -15%
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4
9.7
Hyundai

Free Delivery**
  • Powerful 4.0kW Output: Delivers a continuous 3.5 kW and a maximum 4.0 kW of clean, stable power — ideal for home backup, camping, caravans, events, and small business use.
  • Electric Start & Remote Keyfob: Start your generator effortlessly with a push of a button or the included wireless keyfob for instant power on demand — no manual pull required.
  • Quiet, Enclosed Design: Low-noise operation (approx. ≤60 dB @ 7 m) thanks to the closed-case housing, perfect for residential areas, campsites, and outdoor events.
  • Portable & Easy to Move: Integrated wheel kit and telescopic handle make transport simple, while the compact design ensures easy storage in garages, workshops, or motorhomes.
  • Pure Sine Wave Power with ECO Mode: Provides safe, stable electricity for sensitive electronics such as laptops, TVs, and phones — ECO mode automatically adjusts engine speed for greater fuel efficiency and longer runtime.
Colour Manufacturer Weight
Blue HYUNDAI 47 kg
£76999
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5
9.6
Hyundai

Free Delivery**
  • Powerful & Reliable Performance: Equipped with a 225cc 4-stroke IC225D engine, this portable petrol inverter generator delivers a maximum output of 3800W and a continuous output of 3500W, making it perfect for powering appliances, tools, and sensitive electronics.
  • Quiet & Efficient Operation: With low-noise technology producing just 58 dBA at 7m and an ECO mode to optimize fuel efficiency, enjoy cost-effective and undisturbed power for holidays, events, or emergency use.
  • Versatile Power Options: Features two 230V UK mains sockets, a 12V 5A outlet, and a USB port to charge and power multiple devices simultaneously, from kettles and fridges to laptops and TVs.
  • Portable & Easy to Transport: Compact design weighing only 48kg, equipped with a folding handle, rear moulded grip, and durable wheels for effortless movement and storage in your car, van, or garage.
  • Safe for Sensitive Electronics: Pure sine wave output ensures the safe operation of TVs, laptops, and other sensitive devices without the risk of damage or overload.
  • User-Friendly LCD Display: Monitor performance at a glance with the integrated LCD screen displaying voltage, frequency, and hour count for better control and maintenance planning.
  • Durable & Safe: Includes digital overload protection and low-oil shutdown to safeguard both the generator and connected devices. Built with a robust inverter board for handling high inductive loads.
  • Eco-Friendly & Cost-Saving: The 'ECO' mode automatically adjusts engine speed to match load demand, reducing fuel consumption, noise, and wear for long-lasting performance.
  • Ideal for Leisure & Emergency Use: Perfect for powering caravans, motorhomes, horseboxes, outdoor lighting, and sound systems. Provides dependable backup power for appliances like fridge-freezers during outages.
  • Peace of Mind with Warranty: Backed by a 2-year warranty from P1, ensuring reliability and customer satisfaction.
Colour Manufacturer Weight
Blue HYUNDAI 48 kg
£75557
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6
9.5
Aceup Energy

  • 149cc 4-stroke OHV engine produces 4000 peak watts and 3200 rated watts with recoil start for up to 5 hours at half-load on 1.32 gallon
  • Intelligent gauge keeps track of voltage ,run-time and hertz and track power output, plus feature low oil led and economic mode to save fuel
  • Includes 120V AC one 20A outlets, one RV receptacle, one 12V DC 8.3A car charger outlet; Parallel ready to connect 2 generators for twice the power (parallet kit sold separately)
  • Produce clean power required by sensitive electronics such as phones, TV; Fully-enclosed design reduces noice level
  • 5-in-1 Knob:fuel on/shut-off,engine on/off,choke;When turning off the engine, the fuel switch is turned off at the same time
Colour Manufacturer Weight
Yellow and Black Aceup Energy 21.8 kg
£70010
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7
9.5
JCB

Free Delivery**
  • Powerful, Reliable Output: Impressive max output of 3.6kW / 4.5kVA* thanks to its market leading 7.5hp JCB engine.
Colour Manufacturer Weight
Yellow JCB 50 kg
£39999
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8
9.5
United Power Equipment Co.,Ltd
Save £65.40 Today!
£435.99 (15% OFF!)

Free Delivery**
  • 149cc 4-stroke OHV engine produces 3400 peak watts and 3200 rated watts with recoil start for up to 5 hours at half-load on 5L, 50Hz
  • Intelligent gauge keeps track of voltage, run-time and hertz and track power output, plus feature low oil led and economic mode to save fuel
  • Includes 230V two AC outlets, one 12V DC 8.3A car charger outlet and USB TypeA/C ; Parallel ready to connect 2 generators for twice the power (parallet kit sold separately)
  • This portable pure sine wave generator produces the clean power required by a variety of sensitive electronics such as phones, TV; THD<3%; Fully-enclosed design reduces noice level
  • All generators are functionally tested in the factory to guarantee quality with CE, EURO-V compliant; Backed by a 1 year limited warranty with lifetime technical guidance from experts
Colour Manufacturer Weight
Yellow and Black Aceup Energy 23 kg
£37059
RRP: £435.99 -15%
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9
9.4
maXpeedingrods
Save £50.00 Today!
£849.99 (6% OFF!)

Free Delivery**
  • 【Multifunction Power Supplier】 4 stroke 345cc inverter generator produces 5500W max watts and 5000W running watts. It is easily able to run a huge range of high-power appliances such as 2000W pressure washer, 3000W power tools, an air conditioner with 6000 BTU cooling capacity, refrigerators, kettles, and even more appliances. Or as backup for power outages.
  • 【Low noise】When the generator is in ECO mode at 25% load and is 7m away from the generator, the noise level is 62 decibels. which is almost the quietest generator of this rated power. At this noise level, there is little disturbance for users and people nearby. Please note that ambient noise may affect the overall value of the noise of the machine.
  • 【Extra Long Runtime】13.5L Large fuel tank capacity, runs 9 hours at 50% load (2500w load). In ECO mode, the runtime can be extended up to 13 hours.
  • 【Provide Clean Power】This inverter technology provides more steady power, produces clean power to safely operate and prevent damage to sensitive electronics such as phones, tablets, televisions and computers.
  • [Brand Warranty] Maxpeedingrods warrants all the inverter generators against defects in workmanship under normal use for a period of 2 years from the date of retail purchase by the original end-user purchaser ("Warranty Period"), and free lifetime technical support and customer service.
Colour Manufacturer Weight
Orange maXpeedingrods 52 kg
£79999
Was: £849.99 -6%
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10
9.3
RocwooD

  • Power - The RocwooD RG8000I Generator is powered by a single cylinder OHV four-stroke air cooled engine. The RG8000I exceeds the Euro V standard and the inverter produces 100% clean pure-sine power that is capable of running sensitive electronic equipment.
  • Reliable - You can look forward to 3500 watts of continuous power output, with 4000 watts on tap to cope with the initial draw. This generator can run a huge range of appliances and is ideal for camping. Reliable and powerful at a affordable price.
  • Electric Start - With a built in battery the RG8000I conveniently starts at the push of a button. There is also pull start on offer as a backup. The RG8000I Inverter generator has two approved 230V 16AMP outlets, dual USB sockets for fast charging and a 12V 8AMP battery charging outlet. The RG8000I boasts a huge 6L tank meaning you can expect an impressive running time of over 12 hours at half load or 6 hours at full load and is one of the quietest on the market and idles at just 65 decibels on a 50% load.
  • Transport - You can transport it around with minimum fuss thanks to the sturdy telescopic handle and large all terrain wheels. So whether you need a seriously powerful generator on hand for running tools on the job site, for your motorhome, off-grid cabin, your next camping adventure or as backup for power outages, the RocwooD RG8000I is a workhorse you can rely on.
  • Warranty - This RocwooD product comes with a 12 Month domestic user warranty, business or continuous use will invalidate any warranty. Full warranty terms are available on request before purchase.
Colour Manufacturer Weight
Black RocwooD 48 kg
£78399
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General information about 4000w Generator:

The 4000W Generator: A Reliable Power Source for Various Applications

When it comes to ensuring a steady power supply for different needs, the 4000W generator proves to be a reliable solution. With its capacity to provide 4000 watts of power output, this generator is highly versatile and can cater to a wide range of applications, making it an essential tool for both residential and commercial use.

Powerful and Efficient Performance

Equipped with a robust engine, the 4000W generator is designed to deliver a consistent power supply that meets various power requirements. Whether it's powering household appliances during a blackout or running essential equipment on a construction site, this generator can reliably handle the load. Its impressive power output allows it to run multiple devices simultaneously, providing convenience and flexibility. Additionally, the generator's efficient design ensures optimal fuel consumption, effectively reducing operational costs and extending its runtime.

Versatility for Different Applications

The 4000W generator is a versatile tool that can be used in numerous settings and situations. It is an ideal option for outdoor enthusiasts who require a power source during camping trips or RV adventures. With its portable design, this generator can provide electricity to charge electronic devices, run small appliances, and even power lights, allowing users to enjoy the comforts of home even in remote locations. Moreover, this generator proves to be invaluable during emergencies, ensuring that essential devices like refrigerators and medical equipment continue to function when the regular power supply is disrupted.

Conclusion

In conclusion, the 4000W generator is a reliable and versatile power source suitable for various applications. Its powerful performance and efficiency make it an excellent choice for residential and commercial use. With its ability to handle multiple devices simultaneously and its portability for outdoor adventures, this generator provides convenience and peace of mind. Whether it's for backup power during emergencies or enhancing recreational activities, the 4000W generator proves to be a valuable tool that provides a steady and reliable power supply.

* the possibly used term "best" etc. refers only to our possibly subjective personal opinion.
** "Free Delivery" means that this is possible under the given conditions at the time of data retrieval from the relevant provider, but cannot be guaranteed. It is technically not possible to provide information in real-time. The shipping costs may vary under certain circumstances (different provider, place of delivery, etc.). The shipping costs shown in the further ordering process apply.

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Disclaimer:
1. The prices shown may have risen since the time we last updated them.
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