The best hair straightener will do three things. One, it'll make your hair look as straight or as wavy as you want it to be. Two, it'll do it quickly and with the minimum of fuss. And three, it'll do it without damaging your hair. There's no point looking like you've just stepped out of a salon if you've harmed your hair to do it, so the best hair straighteners in this guide aren't just stylish: they're safe too.
Hair straighteners, also known as flat irons, have two hot plates that you clamp on your hair and then glide smoothly down towards the ends. The heat smooths your hair and then straightens it, and all you need to do is repeat the process until all your hair looks amazing.
It's important to dry your hair before using flat irons or hair straighteners; if you don't, you can inflict heat damage that'll make your hair brittle and harder to style. We'd recommend checking out our guide to the best hair dryers unless you prefer to leave your hair to dry naturally first. And if you're not already a hair straighener expert, our articles on how to straighten hair and how to curl hair with straighteners will tell you everything you need to know.
The cost of hair straighteners can be as low as $20 / £20, but we wouldn't normally recommend going that low unless it's a discounted model that's usually more expensive: the very cheapest hair straighteners tend to cut quality corners and are much less likely to deliver the results that you want. In our guide the cheapest models are a still-affordable $40 / £60, which is where you tend to find the best bargain buys.
You're spoilt for choice when it comes to straighteners: in addition to the big salon names such as GHD and Hot Tools, which started off as salon exclusives, straighteners come from all the familiar hair care brands too such as Remington and Revlon. And there's also Dyson to consider. The firm made its name creating some of the best vacuum cleaners you can buy, but the brand has also used its extensive experience in heat-related products to produce a range of very impressive styling tools. Its first big hit was the Dyson Supersonic hair dryer and the range now includes the Dyson Corrale hair straighteners and the Dyson Airwrap styler.
In this round-up we've put all of the popular designs through their paces (and through our hair) to straighten and curl shoulder length hair; scroll down to see full details of how we tested. Thanks to that testing we're confident that these are the best hair straighteners you can buy right now no matter what kind of hair you have or how much you want to spend.
Best Hair straightener 2022
Why you can trust TechRadar We spend hours testing every product or service we review, so you can be sure you’re buying the best. Find out more about how we test.
How we test hair straighteners
To compare hair straighteners we assess how quickly they heat up, and how effective they are when it comes to smoothing tresses, along with how shiny and frizz-free they left our hair.
We also used the flat irons to style our hair into gentle waves monitoring how easy they are to manipulate and how comfortable and balanced they were to use. We also considered cable length, the range of temperature settings offered and handy features like auto shut-off functions, locks to keep the plates together during storage, and for cordless options, the duration of the battery and how long it takes to recharge.
Best hair straightener FAQs
What to consider when buying hair straighteners
Start by deciding whether you want corded or cordless hair straighteners. Mains-powered models are more affordable than battery-operated options, but they can only be used when an electrical socket is close by. Cordless models, however, can be slipped in your bag and used to touch up your hair part way through the day.
If you’re opting for cordless hair straighteners, look at how long the battery lasts between charges - the models on the market right now offer between 15 and 30 minutes - as well as how long the battery takes to recharge. Most cordless designs can be used while the charging cable is connected, some even offering a swivel connector as you’d find on mains-powered designs, making it easy to create gentle waves in hair.
For mains-powered models, assess whether the cable is long enough to reach from the nearest electrical outlet to where you plan to style your hair.
Hair straighteners come with different widths of plates - narrower options are suitable for fine hair, or those with shorter tresses, while wider plates will be a better option for those with thick hair, or longer locks. The temperature settings of the hair straighteners is also worth considering. If you have fine, or colored hair - look for models that reach lower temperature to protect against heat damage. Whereas thick, coarser hair needs high temperature to ensure every strand is smoothed or curled.
Also look out for features such as a lock which keeps the plates together when the straightners aren’t being used, or a silicon sleeve to protect them during storage, as well as dual voltage, so they can be used in any country in the world, ideal for regular travelers. Also look out for flat irons that have an auto shut off feature, so if you’re forgetful and leave the house without turning them off, you don’t need to worry about them staying on all day.
Are ceramic or titanium straighteners best?
There are two different styles of hair straightener on the market - those with ceramic plates and designs that feature plates made from titanium, which are more affordable.
Ceramic plates use infrared technology to heat the strands of hair from the inside out - this is a gentler way of using heat to style locks, and reduces the damage inflicted on tresses. Titanium plates are more affordable but they heat hair from the outside in, which leaves the hair more vulnerable to heat damage.
Overall ceramic hair straighteners are better for tresses, but if you’re on a budget consider titanium plates only if you’re always willing to use heat protection - whether that’s in the form of a spray, serum or gel. Avoid them if you have very fine or coloured hair, which is more vulnerable to heat damage.
Do hair straighteners damage hair?
Using any heat on your hair will damage the outer protective coating, known as a cuticle layer. Tiny holes will start to appear, and continued use of high heat will see these grow bigger and bigger, with the cuticle layer disintegrating completely, leaving the inner layer of hair strands. When these are exposed, the strands very quickly suffer from breakage.
However, if you want smooth, sleek tresses, or gentle waves and you’re not blessed with the style naturally, using hair tools such as hair straighteners is the only way to achieve these looks. With this in mind, always apply heat protection to your tresses before styling, and opt for the lowest temperature possible that achieves the style with just one pass of the hair straightener, to avoid having to make several passes, which dries hair out and causes split ends.
