| 12301 | January 31 | Event | 1953 – A North Sea flood causes over 1,800 deaths in the Netherlands and over 300 in the United Kingdom |
| 12302 | January 31 | Event | 1957 – Eight people on the ground in Pacoima, California are killed following the mid-air collision between a Douglas DC-7 airliner and a Northrop F-89 Scorpion fighter jet. |
| 12303 | January 31 | Event | 1958 – Explorer program: Explorer 1: The first successful launch of an American satellite into orbit. |
| 12304 | January 31 | Event | 1958 – James Van Allen discovers the Van Allen radiation belt. |
| 12305 | January 31 | Event | 1961 – Project Mercury: Mercury-Redstone 2: Ham the Chimp travels into outer space. |
| 12306 | January 31 | Event | 1966 – The Soviet Union launches the unmanned Luna 9 spacecraft as part of the Luna program. |
| 12307 | January 31 | Event | 1968 – Vietnam War: Viet Cong attack the United States embassy in Saigon, and other attacks, in the early morning hours, later grouped together as the Tet Offensive. |
| 12308 | January 31 | Event | 1968 – Nauru gains independence from Australia. |
| 12309 | January 31 | Event | 1971 – Apollo program: Apollo 14: Astronauts Alan Shepard, Stuart Roosa, and Edgar Mitchell, aboard a Saturn V, lift off for a mission to the Fra Mauro Highlands on the Moon. |
| 12310 | January 31 | Event | 1971 – The Winter Soldier Investigation, organized by the Vietnam Veterans Against the War to publicize war crimes and atrocities by Americans and allies in Vietnam, begins in Detroit. |
| 12311 | January 31 | Event | 1990 – The first McDonald's in the Soviet Union opens in Moscow. |
| 12312 | January 31 | Event | 1995 – President Bill Clinton authorizes a $20 billion loan to Mexico to stabilize its economy. |
| 12313 | January 31 | Event | 1996 – An explosives-filled truck rams into the gates of the Central Bank of Sri Lanka in Colombo, Sri Lanka killing at least 86 and injuring 1,400. |
| 12314 | January 31 | Event | 1996 – Comet Hyakutake is discovered by Japanese amateur astronomer Yuji Hyakutake. |
| 12315 | January 31 | Event | 2000 – Alaska Airlines Flight 261 crash: An MD-83, experiencing horizontal stabilizer problems, crashes in the Pacific Ocean off the coast of Point Mugu, California, killing all 88 aboard. |
| 12316 | January 31 | Event | 2001 – In the Netherlands, a Scottish court convicts Libyan Abdelbaset al-Megrahi and acquits another Libyan citizen for their part in the bombing of Pan Am Flight 103 over Lockerbie, Scotland in 1988. |
| 12317 | January 31 | Event | 2003 – The Waterfall rail accident occurs near Waterfall, New South Wales, Australia. |
| 12318 | January 31 | Event | 2007 – Suspects are arrested in Birmingham in the UK, accused of plotting the kidnap, holding and eventual beheading of a serving Muslim British soldier in Iraq. |
| 12319 | January 31 | Event | 2009 – In Kenya, at least 113 people are killed and over 200 injured following an oil spillage ignition in Molo, days after a massive fire at a Nakumatt supermarket in Nairobi killed at least 25 people. |
| 12320 | January 31 | Event | 2010 – Avatar becomes the first film to gross over $2 billion worldwide. |
| 12321 | January 31 | Event | 2011 – A winter storm hits North America for the second time in the same month, causing $1.8 billion in damage across the United States and Canada and killing 24 people. |
| 12322 | January 31 | Event | 2013 – An explosion at the Pemex Executive Tower in Mexico City kills at least 33 people and injures more than 100. |
| 12323 | January 31 | Birth | 36 BC – Antonia Minor, Greek daughter of Mark Antony (d. 38 AD) |
| 12324 | January 31 | Birth | 877 – Taejo of Goryeo (d. 943) |
| 12325 | January 31 | Birth | 1512 – Henry, King of Portugal (d. 1580) |
| 12326 | January 31 | Birth | 1543 – Tokugawa Ieyasu, Japanese shogun (d. 1616) |
| 12327 | January 31 | Birth | 1550 – Henry I, Duke of Guise (d. 1588) |
| 12328 | January 31 | Birth | 1597 – John Francis Regis, French priest and saint (d. 1640) |
| 12329 | January 31 | Birth | 1624 – Arnold Geulincx, Flemish philosopher and academic (d. 1669) |
| 12330 | January 31 | Birth | 1673 – Louis de Montfort, French priest and saint (d. 1716) |