| 121231 | October 23 | Birth | 1969 – Bill O'Brien, American football player and coach |
| 121232 | October 23 | Birth | 1969 – Brooke Theiss, American actress |
| 121233 | October 23 | Birth | 1970 – Matthew Barzun, American diplomat, United States Ambassador to the United Kingdom |
| 121234 | October 23 | Birth | 1970 – Grant Imahara, American engineer |
| 121235 | October 23 | Birth | 1970 – Steve Wilder, American actor |
| 121236 | October 23 | Birth | 1970 – Zoe Wiseman, American model and photographer |
| 121237 | October 23 | Birth | 1971 – Carlo Forlivesi, Italian-Japanese composer and scholar |
| 121238 | October 23 | Birth | 1971 – Chris Horner, American cyclist |
| 121239 | October 23 | Birth | 1972 – Tiffeny Milbrett, American soccer player |
| 121240 | October 23 | Birth | 1972 – Bryan Pratt, American lawyer and politician |
| 121241 | October 23 | Birth | 1972 – Jasmin St. Claire, Virgin Islander porn actress and director |
| 121242 | October 23 | Birth | 1972 – Jimmy Wayne, American singer-songwriter and guitarist |
| 121243 | October 23 | Birth | 1973 – Christian Dailly, Scottish footballer |
| 121244 | October 23 | Birth | 1973 – Emi Hashino, Japanese comedian and actress |
| 121245 | October 23 | Birth | 1974 – Aravind Adiga, Indian journalist and author |
| 121246 | October 23 | Birth | 1974 – Beatrice Faumuina, New Zealand discus thrower |
| 121247 | October 23 | Birth | 1974 – DJ Spinbad, American DJ and producer |
| 121248 | October 23 | Birth | 1974 – Sander Westerveld, Dutch footballer |
| 121249 | October 23 | Birth | 1975 – Jessicka, American singer-songwriter (Jack Off Jill and Scarling.) |
| 121250 | October 23 | Birth | 1975 – Michelle Beadle, American sportscaster |
| 121251 | October 23 | Birth | 1975 – Odalys García, Cuban actress and singer |
| 121252 | October 23 | Birth | 1975 – Yoon Son-ha, South Korean actress and singer |
| 121253 | October 23 | Birth | 1975 – Keith Van Horn, American basketball player |
| 121254 | October 23 | Birth | 1976 – Cat Deeley, English model, actress, and television host |
| 121255 | October 23 | Birth | 1976 – Ryan Reynolds, Canadian-American actor and producer |
| 121256 | October 23 | Birth | 1977 – Brad Haddin, Australian cricketer |
| 121257 | October 23 | Birth | 1977 – Alex Tudor, English cricketer and coach |
| 121258 | October 23 | Birth | 1978 – Jimmy Bullard, English footballer |
| 121259 | October 23 | Birth | 1978 – Steve Harmison, English cricketer and sportscaster |
| 121260 | October 23 | Birth | 1978 – John Lackey, American baseball player |