What Is Tumble Dry? Here's What The Setting Really Means

Before you press start, it's best to read the fine print.

Louise Parks is a lifestyle writer for Martha Stewart.

Three Spots / Getty Images

If you’ve ever had a garment come out of the dryer several sizes smaller, you know that drying clothes is not always as simple as it seems. There is actually a science behind drying different fabrics, which has given way to a wealth of guidelines and machinery settings by which you can dry your clothes properly and confidently. So before you press start, it's best to read the fine print. What is tumble dry, for instance? And is it suitable for your beloved wardrobe and family's linens?

To help maintain the integrity of your garments, we consulted laundry experts to get the low-down on tumble drying and all of its complexities.

"Tumble dry" instructions are usually listed on a garment's label, represented by a circle within a square. It means your item can be placed in an automatic dryer and machine tumbled until it's dry.

Martha Stewart

As Clorox’s in-house scientist and cleaning expert, Mary Gagliardi, points out, "additional information on a textile item’s care label should tell you what temperature you can safely use to dry the item." Further instructions and symbols on the garment care label usually pertain to washing methods, bleaching, ironing and dry cleaning.

It turns out that all of the settings on your automatic dryer are simply different versions of tumble dry. "The rotating drum tumbles garments continuously to promote even drying and prevent wrinkles," explains Alicia Sokolowski, president and CEO of Aspen Clean.

Typical dryer settings often include timed dry, automatic dry, wrinkle-free, air fluff or no heat, perm press, and delicate, as shared by Gagliardi. "Settings vary depending on the amount of heat and, in the case of newer dryers," she says.

For example, an air fluff cycle tumbles the laundry in room-temperature air. This may not dry wet clothes as well, but is gentle enough for certain fabrics that cannot withstand heat. It also does a great job of removing dust, lint, and pet hair from otherwise-clean pieces. Perm press (or permanent press), on the other hand, references medium-heat with a cool-down cycle to reduce wrinkles—which is great for synthetic blends.

To better understand the cycles on any dryer, consult the original owner’s manual or care guide. Threw it away ages ago? You can often find PDF versions online. "They can be really helpful because of the variability from model to model and manufacturer to manufacturer," Gagliardi explains.

While tumble drying involves letting your dryer do the work, air drying is as old-fashioned as it gets. Choosing between the two can be a critical moment for the future of your garment.

“Your first stop for deciding should always be the care label,” advises Tom Ceconi, president of Heritage Park Laundry Essentials. The label will specify whether or not the garment is safe to tumble dry. If not, it may require air drying. To air dry, opt for line drying or laying the garment flat, depending on what it is. Wool sweaters, for instance, benefit from being laid flat to air dry, as the shoulders can become distorted under the weight of the wet fabric when hung.

Ceconi adds, "Air drying is a great way to prolong the color of clothing, as well as limit shrinkage, even if the item’s label allows tumble drying."

Helin Loik-Tomson / Getty Images

The clothing items most suitable for tumble drying are those that require heat to fully dry and are sturdy enough to withstand the friction and temperature. According to Ceconi, the best items to tumble dry include bath towels, cotton, bamboo, and linen blend sheets, cotton clothing, denim, and synthetic fabrics or blends. Tumble drying is also often required for items with filling, like a down jacket, duvet or comforter, or pillows. (Of course, be sure the label indicates that it's safe to tumble dry.)

Gagliardi recommends tossing some clean tennis balls or wool dryer balls into the dryer to help the load dry thoroughly—and more quickly.

While certain delicate fabrics can tolerate a low-heat tumble dry setting, others need to be treated with extra care. “Tumble dry is not suitable for delicate fabrics like silk, wool, and lingerie, or for clothes with elastic embellishments that may warp or melt,” cautions Sokolowski. In order to maintain the quality of every garment, make sure to read the label before tossing in the dyer, she adds.

Ceconi also cautions against using tumble dry for any compression garments, such as workout or shapewear.

For best results when tumble drying your clothes and linens, adhere to the following tips from our experts.