She first shared a pic of her image next to 19-year-old model Kendall, and unless you real closely, it's almost impossible to tell that Kendall is on the right.
It's gets even trickier to determine who is who when Kim put her pic up against her 17-year-old sister Kylie's face. Can you tell which face belongs to Kim?
Kim and Kylie have more in common than just looking alike. The 34-year-old reality star told ET that her youngest sister is a kindred spirit.
"She is the best, you know? She's my little twin soul," Kim said of Kylie. "She's such a free spirit, and I love that. She's the sweetest."
Kendall and Kylie also revealed to ET the best beauty tips they've ever received from their older, style-savvy sisters. "I love Kim's style right now," Kylie complimented. "…I feel like Kourtney has the best style overall."