Final Verdict

While we were skeptical about its ease of use at first, the T3 SinglePass Luxe impressed our testers the most with its straightening ability, heat settings, and durability. For those looking to splurge, look no further than the Dyson Corrale; its innovative flex plates and rapid heat up time will be sure to impress you. However, if you’re looking to save some pennies the Hot Tools Signature Series Ceramic Digital Flat Iron will get the job done for less than $50.

How We Tested

We spent two weeks researching flat irons, interviewing experts, and reading product reviews to land on the product selection. Once the team narrowed down the tools in consideration, it was time to put them all to the test. Our editor created a standardized methodology for the testers to test each iron and collected insights on each. Each flat iron was rated on a 1-5 scale for glide performance, straightening ability, and temperature settings.

Since every type of hair has a different experience with a hair straightener we had three testers with different hair try each of these flat irons. We tested on fine hair, wavy and thick, and type 4 textured curls.

Our testers took note of how smooth the glide felt and how many passes it took to get their hair straight. We utilized a meat thermometer to test the maximum heat and used a stopwatch to time how long each iron took to heat up and shut off automatically. We also tested durability by dropping each iron twice at vanity level to see if it would break, chip, or scratch. After collecting the data, our editor assigned categories for each item and product placement within the list. All testing was conducted at The Lab, located in Industry City in Brooklyn.

Other Options We Tested

Remington Pro 2″ Flat Iron with Thermaluxe

The Remington Pro 2″ Flat Iron claims to only be able to reach a temperature of 450 degrees. However, our thermometer read 473 degrees—a substantial difference. While in use this one worked in one to two passes for our fine-textured testers but for our tester with coarse hair, not so much; it actually smoked up a lot and made us a little nervous to have her continue using it.

CHI Original 1” Ceramic Hairstyling Iron

While CHI is such a well-known brand—our testers have all used a CHI Iron at some point in their lives—we couldn’t add the Chi Original 1″ Iron to our list. All three testers’ feedback was that the iron took multiple runs to straighten their hair. “The plates of this product didn’t line up properly, so it was difficult to straighten my hair; I had to press very hard several times to straighten wavy strands,” says one tester. Plus, there is no display screen or automatic shut-off.

Conair Double Ceramic Flat Iron

It took our fine and wavy hair testers only one or two passes to get a sleek look with the Conair Double Ceramic Flat Iron, which was good but we can’t say the same about our type 4 hair tester. It would have taken multiple passes, but we stopped after three to avoid any damage. Plus, the brand does claim that this tool has an automatic shut-off, though it wasn’t mentioned how long. We left the iron powered on for two hours and it was still on, so if it does have this feature, it takes more than two hours to activate it.

Bio Ionic OnePass Straight Iron

While using the Bio Ionic OnePass Straight Iron our testers found that, while it did straighten the hair in one or two passes, their strands felt dry and unhealthy afterward. All three testers couldn’t justify spending $200 for something that made their hair feel so unhealthy.

BaByliss Nano Titanium Straightening Iron

Two of our testers reported that the BaByliss Nano Titanium Straightening Iron made their hair feel brittle and unhealthy and needed two or three run-throughs to get it straight—and, when it came time for the third tester to try the tool, it didn’t even heat up! We’re not sure exactly what happened, but we continued with the durability test, and with one vanity-level drop, a piece broke off the flat iron. For $150, we can’t say it’s worth it.

What To Look For in a Flat Iron

Plate size

Flat irons come in all different sizes. One-inch plates are perhaps the most commonly found size, great for making loose waves and tight curls, that is if you’re not just looking for super sleek hair. The larger the plates get (1.5 inches, 1.75 inches, or 2 inches+), the easier it will be to straighten long, curly, coarse, and thick hair in less time. If you wish to style bangs or shorter hairs, reach for a plate size that’s less than one inch as it will be easier to get close to your scalp. If you’re not sure which plate size is right for you, we recommend opting for one-inch plates as it’s the most versatile option.

Adjustable heat settings

According to Maine, nearly any time you sandwich hair between two hot plates, it’ll straighten. “I believe heat settings are important so that you can customize the iron to your specific texture,” he says. “Damaged and highlighted textures should use a lower temperature.” If you aren’t sure what temperature is suited for your hair type, brands like GHD take the guesswork out by suggesting that 365 degrees is the optimal temperature for most hair.

Fast heat-up

Finding a tool that heats up quickly is also important, as it’s a good indication that the heat will also be distributed evenly and consistently, which, you guessed it, also minimizes damage.

Durability

Flat irons are an investment and many of them come with a hefty price tag. “Flat irons are the single most-used hot tool,” says Maine. “It’s important they last and are sturdy as we accidentally knock them off the counter or let them get tossed around in our luggage. A good straightener should last years.”

Ease of use

Maine believes a flat iron should glide easily throughout the hair. “You want to find one whose plates have a glossy coating or smooth ceramic,” he says. Pro tip: If you like to use yours for a variety of styling options, like waves and curls, be sure to select one with rounded edges that meet the edges of the plates.

Why Trust Byrdie

Byrdie’s Beauty Review Editor Angela Trakoshis has more than five years of experience in beauty journalism. She has tried and researched countless flat irons and has been personally using one since she was 12 years old. For this story, she recruited three testers with different hair types—Senior Commerce Editor Avery Stone, Associate Editor Eden Stuart, and Commerce Production Assistant Sam Aronson—to test every flat iron. Each tool was graded upon the same scale and tested one after another on different pieces of hair. She also interviewed stylists and spent hours conducting her own product research and testing the durability, heat settings, and more attributes of each iron.

According to our Diversity Pledge, 15% of products in our newly-published market roundups will feature Black-owned and/or Black-founded brands. At the time of publishing, we weren’t able to find any flat irons from a Black-owned and/or Black-founded business. If you know of one we should consider, please email us at contact@byrdie.com and we will evaluate the product ASAP.