So I searched up the black and blue dress : r opticalillusions Women's Black And Gold Dresses REVOLVE Black and Gold Maxi Dress ethnic Dress long Dress woman Dress Evening Dress Sexy Dress Tight Dress Body Corn open Back Dress Embroidery Etsy Baltic Born Womens Azura Gown Black + Gold Color: Black and Gold Size: Small 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