When tackling outdoor cleaning tasks like washing your car, deck, patio or driveway, a pressure washer is an invaluable tool that can blast away even the most stubborn dirt and grime with ease. But traditional gas or electric pressure washers require cords and hoses that restrict your movement.

This is where the magic of cordless pressure washers come in. They provide the convenience of being completely portable – you can carry them around one handed to wherever the cleaning is needed. The best models now pack enough pressure punch on par with some light to medium duty corded versions.

Before choosing your ideal cordless washer, here’s a guide to the key things you should consider:

Battery Voltage and Life

Cordless pressure washers are powered by built-in lithium-ion batteries and the two most common voltages are 18V and 20V. Some of the heavier duty models may also feature a pair of 18 or 20V batteries hooked up together to drive a more powerful motor.

In most cases, a model with a 20V battery performs stronger with a higher pressure level compared to an 18V counterpart. Get a 20V model if power is your priority.

Batteries with higher voltages also deliver better runtime per charge so your spraying time lasts longer before needing a recharge. The average spraying duration on a charge is 20 minutes for entry-level 18V models whereas high end 20V units can fire continuously for close to an hour.

Having a backup battery which you can swap out after the first is spent definitely maximises spraying uptime and productivity. Some brands offer the cordless pressure washer as part of a kit bundled with an extra battery.

Pressure Rating (Bar)

The cleaning power of pressure washers is measured in bar or psi (pounds per square inch). 1 bar equals to roughly 15 psi.

Gas models generate up to 3000 psi but even tough dirt stains can be dislodged with 1500 psi. On a cordless washer running off battery juice alone, the maximum pressure is much lower ranging from 70 psi (or 20 bar) for the basic models to 160 psi (60 bar) for pro grade units.

The higher the bar, the higher the pressure and stronger the spray power allowing you to complete tougher cleaning tasks faster and more easily.

Most battery-powered models have a pressure output between 30 to 60 bar which is adequate for siding, decks and driveways. If you also need to strip paint, choose the ones rated over 50 bar.

Adjustable Nozzle Spray Patterns

Another handy feature available on most cordless pressure washers is the ability to switch between different spray patterns. This is achieved via a multi-mode nozzle or jet spray lance with adjustable settings typically 15, 25, 40 and 60 degrees.

The 15 or 25 degree jets concentrate the hardest water pressure on a focused spot, resulting in a powerful stream perfect for blasting away ground in dirt or stripping paint and grime off concrete. But they may damage delicate surfaces if not used carefully.

The 40 or 60 degree wide spray patterns evenly distribute the water pressure over a larger area. They are gentler for washing cars, outdoor furniture, siding, decks and other finished surfaces you don’t want to mar. The trade off is having a less intense jet stream.

Make sure the model you pick contains a variable nozzle so you have the versatility of both high pressure pinpoint cleaning and a wider scrubbing pattern.

In a Nutshell

Cordless electric pressure washers offer robust cleaning capacity without the hassle of dragging hoses and cables around. Models with higher voltage batteries, bars of pressure and adjustable multi-mode wands give you the best bang for the buck.

Keep an extra charged battery on standby so you can swap it in after the first depletes. This lets you maximise working time and complete big cleaning tasks without disruptive downtime waiting for batteries to recharge.