To determine if a website is legitimate, check if it has its contact information, such as address, phone number and registered business name, readily available. Also, check that the phone number is legitimate by calling it. Use whois.net to determine if a particular company owns a domain name.
Another way to determine if a website is legitimate is researching it with the Better Business Bureau. Do searches on reputable website review pages to investigate the questionable website. Searching Google or Yahoo for the website is also a good idea. If there are few results, the site could be a scam. Also, a legitimate business website with secure shopping is secured with a payments page that has Secure Sockets Layer, or SSL. SSL pages begin with "https," not "http."
Just because a website looks legitimate or professional, doesn't mean it is. Check that the photos, text or graphics aren't stolen from another website. Web sites that aren't legitimate are typically vague and inaccurate with information, whereas legitimate websites are succinct and give accurate information.
A poorly designed website is also a sign that it isn't legitimate. Check the links on the site, and if many of them are broken, it is a poorly designed page that was likely thrown together in a hurry. If some of the links redirect you to a different website, this is another sign of a scam.