A hair diffuser spreads a dryer's airflow so curls set in their natural shape instead of blowing apart. Here are four attachments, four dryers that come with one and the foams I would diffuse over.
How to Use a Hair Diffuser, Plus the Dryers and Foams That Make It Work
The diffuser became a curl essential after Lorraine Massey's Curly Girl: The Handbook came out in December 2001, when straight hair was the prevailing style and many women felt pressed to flat-iron or relax their curls. Her routine called for diffusing curls on low heat instead of blasting them straight, and it grew into an online community that spread across YouTube, Reddit and TikTok. A hair diffuser works by spreading the airflow over a wide bowl of prongs, so each curl dries in its own shape with less frizz. ghd, the brand three hairdressers started in 2001 and which moved into dryers in 2012, makes the diffuser I would try first if you already own its dryer. Drybar's Bouncer slows the air down, Bio Ionic's universal version is made to fit most dryers, and Harry Josh, the Vancouver-raised stylist whose career took off after a full-page Vogue feature in 2002, makes his for the Pro Dryer 2000, which is hand-made in France. Check the nozzle size before you buy an attachment on its own.
Dryers that come with one
If you are replacing a dryer anyway, buy one with a diffuser in the box. Curlsmith grew out of an online community of people with textured hair who were invited to weigh in on formulas, scents, packaging and even the name, and its Defrizzion dryer comes with an extra-large diffuser to reduce heat damage. Alli Webb started Drybar with a mobile blowout service before opening the first bar in Brentwood in 2010, and the Buttercup PRO is the take-home version of that salon. Bio Ionic was founded in 1997 by the stylist Fernando Romero, who says he discovered natural negative ions while traveling in Japan, and the Smart-X uses more air and less heat. Shark Beauty, the beauty arm of SharkNinja, makes the FlexStyle, a styler that dries, curls and smooths, and its curly hair set comes with a diffuser.
What to diffuse over, and the skip
Foam gives curls something to hold onto while they dry. Bumble and bumble is the salon brand Michael Gordon founded in 1977, and its curl mousse uses oils and butters for bouncy curls. Oribe Canales, the Cuban-born stylist behind so much supermodel-era hair, lent his name to a curl shaping mousse for waves and curls. Verb began in Austin barbershops because the salons sold products to only about 2 percent of customers, and its foaming gel defines without crunch. Ouai's foam, from Jen Atkin, works on days you skip the dryer entirely. What I would skip is moving the diffuser around while you dry. Cup the hair into the bowl, hold it still, then move to the next section, or you undo the curl definition you just built.
Getting the timing right
Apply foam to soaking wet hair, then diffuse on medium heat and gentle speed until your hair is about 80 percent dry. Let the rest dry on its own so the curls stay soft. Scrunch out any crunch at the end with a drop of oil. The first try takes longer, but it gets faster within a week.
