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
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The GHD Unplugged strikes the right balance between portability and performance, which in our eyes makes them the best hair straighteners you can buy right now. The cordless flat irons are extremely compact, so they can easily be slipped into a bag to touch up your hair throughout the day. They only offer one temperature setting: 365 F / 185 C. GHD claims any hotter will cause serious heat damage, which is definitely true when it comes to fine hair, while styling below this temperature will often require many passes of the tool to achieve a good result, which dries out the hair, causing split ends.
We were impressed with the hair straightener both when smoothing and curling hair. It only requires one pass to leave our tresses smooth and shiny, while the lightweight styler is easy to manipulate when styling our locks into gentle waves.
At 0.8 inches / 2cm wide, the plates are narrower than many others in this list, which won’t suit those with particularly thick hair, while at 20 minutes the battery life is shorter than the Dyson Corrale cordless straighteners (see below). There’s also no lock to keep the plates clamped together when not in use. That said, these really are minor gripes on what is the best pair of hair straighteners we’ve tested.
Read our full review: GHD Unplugged
For those that want cordless hair straighteners, these are the best you can buy, but at an eye-watering $499.99 / £399.99 RRP, they are the most expensive flat irons on the market right now. They can be used on battery power, for up to 30 minutes; however, if your styling session takes longer, they can also be used when connected to the charging cord, which has a 360 degree swivel connector so they can easily be manipulated when straightening or curling hair.
On test, the straighteners took just one pass on the lowest temperature setting to smooth our fine tressess, although the straighteners offer three heat settings in total making them suitable for thicker hair too. Unlike the GHD Unplugged - the other cordless hair straightener we’ve tested in this round-up (above) - the Dyson Corrale offers a clear battery level, too.
However, as hair straighteners go, they’re heavy, we found we got arm ache after curling a whole head of hair. The industrial design isn’t the sleek look we’d expect either - while some will love it, others will hate it.
Read our full review: Dyson Corrale
If shiny tresses are a priority, the Panasonic EH-HS99 straighteners are ideal as they use moisture from the air to charge ions, which are applied to the hair to decrease frizz and introduce shine. On test, the plates certainly boost the shine of our locks, while also smoothing them in just one pass.
Quick to heat up, the EH-HS99 also features a lock to keep plates together when they’re not in use, making the hair straighteners easy to store. However, they certainly don’t look as stylish as some hair straighteners in this list - in fact, we found the construction didn’t give off the air of a premium device, so you’ll feel like you’re buying a cheaper set.
The hair straighteners also lack any audible alerts, when they’re reached temperature, something many other models offer including the GHDs above, and the plates didn’t glide as smoothly through our tresses as others we’ve tested.
Read our full review: Panasonic EH-HS99 hair straighteners
If you’re on a budget, these Hot Tools straighteners are some of the best we’ve tested that come with a relatively affordable price tag. They use titanium, rather than ceramic, plates to keep the price down - but as these heat from the outside in, they leave the hair more vulnerable to heat damage. So if your hair is very fine, or colored, we’d advise using this model with extreme caution.
During testing, we found the hair straighteners were simple to use, and glide through hair smoothly, straightening locks in just one pass. With 14 different temperatures to choose from, they’ll work well on thicker hair too, and they’re compatible with both 110 and 240V, making them ideal for travelers who want to take them out of the country.
However, they were lacking a lock to keep the plates together, making them harder to store, and the auto shut off takes a whopping 120 minutes to kick in - almost double the time of other hair straighteners we’ve tested.
Read our review: Hot Tools Pro Signature Digital Straightener
For those with colored hair or tresses that are vulnerable to heat damage, these hair straighteners from Revlon are ideal as they can drop to as low as 195 F/90 C for styling.
When it comes to heat settings, there’s an impressive 29 temperatures to pick from - rising all the way to 455 F / 235 C. On test, the plates of the Revlon Pro Collection Salon Straight Copper Smooth Extra Long Styler glide easily through our fine hair, requiring just one pass to smooth tresses. We also loved that you can store the last used temperature, so you don’t have to spend time resetting the heat every time you switch the hair straighteners on.
However, there are some compromises. The tip of the straighteners is squared off, rather than tapered, which means it was hard to get close to the roots when styling. We also found the length of the straighteners meant they were bulky, making them unwieldy to use
Read our full review: Revlon Pro Collection Salon Straight Copper Smooth Extra Long Styler
If you want a hair straightener that can smooth your locks but also moisturize them at the same time, then look no further than the Remington Hydraluxe Pro Straightener S9001. It comes with a tiny 0.24 fl oz / 7ml water tank, which emits a fine mist of cool water onto tresses after they’ve been straightened to cool and rehydrate them.
The straighteners glide easily through our hair and leave our tresses smooth. Even better, there’s a temperature boost button that will quickly raise the heat to 450 F / 230 C, to style stubborn sections.
However, the water tank design means the straighteners are bulkier than most, making them hard to grip, especially when curling hair. Speaking of the water tank, it's fiddly to fill - the straighteners come with a pipette but we didn’t find this very useful.
Read our full review: Remington Hydraluxe Pro Straightener S9001
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.