21 December 2023

• 355th day of the year. There were then 10 days left in 2023.
• 51st Thursday of 2023.
• on the 51st week of 2023 (using ISO standard week number calculation).
• Birthstone for this day: Turquoise & Blue Topaz

There are no major holidays or observances in New Zealand for this date.

• Beginning of Winter (Winter Solstice) - Venezuela, United States, Mexico, Colombia, Canada
• Gravy Day - Australia
• Summer starts (Inicio del Verano) - Peru