Confused by how big your dehumidifier needs to be? Follow these simple sizing rules

A modern home office with a swivel chair and a white dehumidifier plugged into the wall
DUUX Bora Smart Dehumidifer 30L, £349.99 (Image credit: DUUX)

When it comes to choosing a dehumidifier, capacity really does matter. Pick one that’s too low, and it’ll run constantly while barely reducing humidity. Go too high, and you could end up using more energy than you need. As with all things, the goal is to hit that Goldilocks number: the best dehumidifier that’s just right for your home and how you use it.

The right capacity depends on the size of your home, how damp the space is, and what you need the unit to do. Whether you’re trying to tackle window condensation, improve air quality or dry laundry indoors, knowing what size of dehumidifier you need will help you get better results with less waste.

Headshot of Nicholas Auckland from Trade Radiators
Nicholas Auckland

Nicholas Auckland, Managing Director at Trade Radiators, is a heating and energy expert with nearly 20 years of experience. He’s known for helping homeowners find practical, energy-efficient solutions, whether it’s choosing the right radiator or picking a dehumidifier that cuts down on damp and running costs.

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Katie Lilywhite

Katie is one of the many experts at AO.com, covering a multitude of appliances including air quality products, health and beauty and homes and gardens.

Headshot of Chris Michael Director at Meaco (U.K.) Limited
Chris Michael

Chris and his partner Michelle started Meaco in 1991. Meaco is now regarded internationally as a major player in the dehumidifier industry selling to 20+ countries throughout Europe, North America and South Africa.

Gabriella Dyson
Interiors journalist and contributing editor

Gabriella is an interiors journalist and has a wealth of experience creating interiors and renovation content. She was Homebuilding & Renovating's former Assistant Editor as well as the former Head of Solved at sister brand Homes & Gardens, where she wrote and edited content addressing key renovation, DIY and interior questions. 

She’s spent the past decade crafting copy for interiors publications, award-winning architects, and leading UK homeware brands. She also served as the Content Manager for the ethical homeware brand Nkuku.

Gabriella is a DIY enthusiast and a lover of all things interior design. She has a particular passion for historic buildings and listed properties, and she is currently in the process of renovating a Grade II-listed Victorian coach house in the West Country.