Reviewers agree that if you want it fitted, size down.
Promising reviews: “I saw this girl wearing this exact style of dress with a Skims tag on the back, and honestly, it made me so grateful that I purchased this dress instead. It looks exactly like the Skims version, and I could be biased, but the material of this dress looked better than the Skims one. If you want it to be a little snug, I would definitely recommend sizing down one size from your normal size. So freaking comfortable and made out of thick material.” —Kaitlyn
“I have the Skims dress in black and wanted to look for a cheaper version, but read reviews and some said that it is a bit looser than expected. I would agree that the small is a bit loose. If you want a snatched look definitely get a size smaller as it is very stretchy. I’m 5′ tall so this is a bit long on me, even when I wear heels. In comparison to the Skims, the material is smoother while Skims has a ribbed texture. You honestly can’t tell the difference. Good bang for your buck if you ask me!” —Amazon Customer
Get it from Amazon for $24.99 (available in sizes XXS–XL and 10 colors).