Halloween is just a few weeks away, but it looks like a few of our favorite celebrities have already dressed up for the spooky holiday. Justin Bieber, Katy Perry, Miley Cyrus, Ariana Grande and more stars have all stepped out in outrageous outfits that we accidentally mistook for costumes. (A certain someone who's friends with Justin wore a legit costume to lunch one day! Click to photo 12 to see who we're talking about.)
So if you still don't know what you're going to be on October 31, we recommend checking out these stars' over-the-top looks for some inspiration.
Click through the above gallery to see 15 outfits we thought were costumes, and then vote for the craziest in the comments.