What is your hair type and condition? Those with thick, coarse hair should look for irons that get very hot and transfer heat well, like those with titanium plates. Buyers with fine hair should shop for an iron with temperature settings that can be set very low and that are adjustable, according to Folica.com. Those with medium-thick, wavy or curly hair will likely be fine with the basic temperature setting on most irons.
What kind of hairstyle are you trying to achieve? Wide plates help cut down on styling time for those with very long hair, but they don't work as well on short hair, according to Stylebell.com. Narrow plates are good for short hair, detail pieces (like bangs) or for curling or flipping hair. If you change your hairstyle often, a 1-inch plate tends to be the most universal.
Do you travel often? If you travel overseas, a dual-voltage flat iron may be a priority, though they're not widely available. You may also want to reconsider how much you're willing to spend on a flat iron if you have to purchase one for home use and a second for travel. Size is also a consideration when traveling, but not all dual-voltage irons are small, according to Folica.com.
How experienced are you? If you've never used a flat iron before, you may want to consider looking at the lower end of price range. Invest in a pricier model once you've identified which features really matter to you, including temperature, adjustability, automatic shutoff, etc. A professional stylist may also be able to help instruct you on temperature and plate material recommendations for your hair.