Most tourist kimono are made of two types of material, cotton or satin. The satin "kimono" are much easier to spot. But sometimes it can be hard to tell the difference between a cotton tourist kimono and a real yukata because they are both made of the same material. So let's take a look at some touristy satin kimono first.
As you get more familiar with seeing kimono, certain patterns will start to immediately pop out at you as not Japanese. Large patterns embroidered on the back are probably fake (dragons, pagodas, geisha, etc). Kimono patterns are designed with the obi in mind. So a pattern that crosses your back would be hidden behind the obi!
If you can get close enough to see the details of the kimono, this is the best way to tell a tourist kimono from an authentic kimono. Here are some things to look for.
First, the collar of a kimono is made with the same fabric as the body of the kimono. If you see they are made from two different fabrics or colors, then it is either fake, or possibly a juban (underwear for kimono that often has a white collar).
Another key feature is that kimono are made from one size bolt of fabric
Also notice how the sleeves make a T shape with only a small opening on the outside for your arm to go through. The rest of the sleeve on the outside is sewn shut. Notice how the red kimono below has normal sleeves that are tube shaped and are completely open at the end. In addition, it lacks the seam running down the back. This is how you know it's not authentic.
Many fakes can be spotted before you even look at the picture. When buying online, be on the look out for items listed using many different words describing various cultures. When the seller doesn't even know what they're selling, you probably shouldn't buy from them. Examples include:
Black Ancient Chinese Calligraphy Silk Satin Kimono Robe
Retro kimono Chinese Yukata Kimono Obi Cosplay Peacock Robe Geisha Dress
Japanese Geisha Bath Robe Nightwear Chinese Kimono Dressing Night Gown One Size
Occasionally authentic kimono will be sold using this method just to get more hits on their product. But if you're not sure, it's probably better to avoid these.
You should always try to be familiar with the clothing of other countries that may be similar to kimono. This will really help you to make sure when you buy your first kimono, you're not actually buying Chinese hanfu. Below I have included a small selection of photos of other Asian clothing for comparison.
Now you may be wondering, how do you search for authentic kimono online without having to wade through all the fakes? Your best bet is to find sellers who only sell authentic kimono and bookmark these stores. Alternatively, if you're using a website like ebay, you can use specific search terms to help narrow down the listings. Terms like "iromuji" or "komon" will immediately filter out almost all of the fake kimono. If you don't know any of these terms you can refer to my post on the different types of kimono here (article still being written). Or you can see my list of various online kimono sellers to help get you started.
Sometimes even the experts can be stumped on a kimono. And even if a kimono is fake or a "tourist kimono" you can still wear it! They make really good pajamas for wearing in your house. Some pieces that are technically not authentic kimono can still be beautiful and worth converting into a kimono or wearing as is. Just be aware of what you have if you're going to wear it outside.
If you have any more questions in general or about a specific item, please feel free to ask.