Taylor Swift's engagement ring is estimated to be approximately 13 carats, according to a gem expert who analyzed the ring and noted that the size aligns with Swift's favored number 13. The diamond is an antique brilliant cut with a D color grade and high clarity, set in a vintage yellow gold band with intricate filigree designs. Other estimates from various sources range between 7 to 10 carats or 8 to 12 carats, but the prominent expert view highlights 13 carats as likely and symbolically significant to Swift. The ring was designed by Kindred Lubeck of Artifex Fine Jewelry in New York City and is valued around $650,000 or more based on its size, quality, and unique vintage characteristics.