The dress is black & blue, but here's why you can't tell TJ Kelly A scientific tale of two dresses CNN Blue and black or white and gold? A decade later, it turns out the ultra viral optical illusion dress was also a boon to scientific advancement. See link below The actual dress was black and blue. The confusion came from how lighting and color perception tricked people's brains, making some see it as white and gold. It became a viral example Mermaid Navy Blue Prom Dresses Lace Sweetheart Satin Slit alinanova Prom Dress Style #33651 La Femme