What Day Of The Week Is December 21?

December 21: Day of the Week

December 21, 2026 is the 355th day of the year 2026 in the Gregorian calendar. There are 10 days remaining until the end of the year. The day of the week is Monday.

If you are trying to learn Japanese then this day of the week in Japanese is Getsuyōbi.

Here’s the December calendar. You can also browse the full year monthly calendar.

December					2026
Sun	Mon	Tue	Wed	Thu	Fri	Sat
1	2	3	4	5
6	7	8	9	10	11	12
13	14	15	16	17	18	19
20	21	22	23	24	25	26
27	28	29	30	31

It’s game time! 🎰 I've got a fun challenge for you—can I guess your date of birth in less than 20 tries? Here’s how it works: I’ll give you a series of dates, and based on your answers, I’ll try to figure out your special day 🎂 It’s all in good fun, and it’s all about you! 🥳 Give it a shot, and let’s see if I can nail it down with this birthday guessing game 🎉 (Sponsored by MyBirthday.Ninja)

Zodiac & Birthstone

Sagittarius is the zodiac sign of a person born on this day. Turquoise is the modern birthstone for this month. Onyx is the mystical birthstone from Tibetan origin that dates back over a thousand years.

December 21: This Day in History

This is a frequent day for the winter solstice to occur in the northern hemisphere and summer solstice to occur in the southern hemisphere.

December 21 by the Numbers

• 309 days since December 21
• 0 year, 10 months, and 6 days ago
• 10 months since then
• December 21 is in the 52nd week of the year 2026 (ISO 8601)
• 44 weeks ago
• The year 2026 is not a leap year

December 21 Historical Event(s)

1140Conrad III of Germany besieged Weinsberg. 1844The Rochdale Pioneers commence business at their cooperative in Rochdale, England, starting the Cooperative movement. 1883The first Permanent Force cavalry and infantry regiments of the Canadian Army are formed: The Royal Canadian Dragoons and The Royal Canadian Regiment. 1907The Chilean Army commits a massacre of at least 2,000 striking saltpeter miners in in Iquique, Chile. 1910An underground explosion at the Hulton Bank Colliery No. 3 Pit in Over Hulton, Westhoughton, England, kills 344 miners. 1962Rondane National Park is established as Norway’s first national park. 1968Apollo program: Apollo 8 launched from the Kennedy Space Center, placing its crew on a lunar trajectory for the first visit to another celestial body by humans. 1994Mexican volcano Popocatepetl, dormant for 47 years, erupts gases and ash. 1999The Spanish Civil Guard intercepts a van loaded with 950 kg of explosives that ETA intended to use to blow up Torre Picasso in Madrid. 2004Iraq War: A suicide bomber killed 22 at the forward operating base next to the main U.S. military airfield at Mosul, the single deadliest suicide attack on American soldiers.

Who were born on December 21?

1795Leopold von Ranke, German historian (d. 1886) 1843Thomas Bracken, Irish-born New Zealand poet (d. 1898) 1872Don Lorenzo Perosi, Italian composer (d. 1956) 1890Hermann Joseph Muller, American geneticist and Nobel laureate (d. 1967) 1920Jean Gascon, Canadian actor (d. 1988) 1952Joaquín Andújar, Dominican baseball player 1955Jane Kaczmarek, American actress 1972Erwin Schrott, Uruguayan opera singer 1972Gloria De Piero, English journalist 1989Tamannaah, Indian actress

It’s game time! 🎰 I've got a fun challenge for you—can I guess your date of birth in less than 20 tries? Here’s how it works: I’ll give you a series of dates, and based on your answers, I’ll try to figure out your special day 🎂 It’s all in good fun, and it’s all about you! 🥳 Give it a shot, and let’s see if I can nail it down with this birthday guessing game 🎉 (Sponsored by MyBirthday.Ninja)

Now try another date like anniversaries, birthdays of someone you know or any other date that is special to you. Don’t forget to share the info to your friends, loved ones or social media followers. Who knows, they might appreciate and thank you for it.

Share this page: