| 9091 | January 21 | Birth | 1986 – Jonathan Quick, American ice hockey player |
| 9092 | January 21 | Birth | 1986 – Sushant Singh Rajput, Indian actor |
| 9093 | January 21 | Birth | 1987 – Ioannis Athanasoulas, Greek basketball player |
| 9094 | January 21 | Birth | 1987 – Augustine Kiprono Choge, Kenyan runner |
| 9095 | January 21 | Birth | 1987 – Henrico Drost, Dutch footballer |
| 9096 | January 21 | Birth | 1987 – Darren Helm, Canadian ice hockey player |
| 9097 | January 21 | Birth | 1987 – Mulopo Kudimbana, Congolese footballer |
| 9098 | January 21 | Birth | 1987 – Maša Zec Peškirič, Slovenian tennis player |
| 9099 | January 21 | Birth | 1988 – Ashton Eaton, American decathlete |
| 9100 | January 21 | Birth | 1988 – Vanessa Hessler, Italian-American model and actress |
| 9101 | January 21 | Birth | 1988 – William C. Woxlin, Swedish actor, playwright, and composer |
| 9102 | January 21 | Birth | 1989 – Doğuş Balbay, Turkish basketball player |
| 9103 | January 21 | Birth | 1989 – Henrikh Mkhitaryan, Armenian footballer |
| 9104 | January 21 | Birth | 1990 – Corey Lof, Canadian actor |
| 9105 | January 21 | Birth | 1990 – Jacob Smith, American actor |
| 9106 | January 21 | Birth | 1993 – Chiara Pierobon, Italian cyclist (d. 2015) |
| 9107 | January 21 | Birth | 1994 – Booboo Stewart, American actor, singer, and dancer |
| 9108 | January 21 | Birth | 1994 – Kang Seung-yoon, South Korean singer-songwriter and actor |
| 9109 | January 21 | Birth | 1994 – Marny Kennedy, Australia actress, singer, and model |
| 9110 | January 21 | Birth | 1995 – Andrew Watson, Northern Irish racing driver |
| 9111 | January 21 | Birth | 1997 – Jeremy Shada, American actor and singer |
| 9112 | January 21 | Birth | 2001 – Jackson Brundage, American actor |
| 9113 | January 21 | Birth | 2004 – Princess Ingrid Alexandra of Norway |
| 9114 | January 21 | Death | 496 – Epiphanius of Pavia, Italian bishop and saint (b. 438) |
| 9115 | January 21 | Death | 917 – Erchanger, Duke of Swabia (b. 880) |
| 9116 | January 21 | Death | 1118 – Pope Paschal II (b. 1050) |
| 9117 | January 21 | Death | 1527 – Juan de Grijalva, Spanish explorer (b. 1489) |
| 9118 | January 21 | Death | 1546 – Azai Sukemasa, Japanese daimyo (b. 1491) |
| 9119 | January 21 | Death | 1609 – Joseph Justus Scaliger, French historian and scholar (b. 1540) |
| 9120 | January 21 | Death | 1638 – Ignazio Donati, Italian composer (b. 1570) |