r/todayilearned • u/St_Gregory_Nazianzus • 2h ago

TIL that in 1943, a U.S. Navy destroyer accidentally fired a live torpedo at the battleship carrying President Roosevelt. The USS Iowa managed to evade the torpedo, and the destroyer's crew initially tried to warn the battleship using signal lamps before breaking radio silence to alert them

militarytimes.com

1.6k Upvotes

85 comments

r/todayilearned • u/Sensitive_Ad_1752 • 3h ago

TIL Boxing promoter Don King beat an employee to death in 1966 because he owed him 600 dollars. Decades later he tried to rename the street where he murdered him after himself “Don King Way”

cleveland.com

3.7k Upvotes

165 comments

r/todayilearned • u/UltimateOreo • 5h ago

TIL that in 2003, MIT scientists unveiled a biological weapons detector funded by the U.S. military that hijacked living white blood cells, genetically engineering them to glow when they encountered deadly pathogens like anthrax.

news.mit.edu

1.1k Upvotes

31 comments

r/todayilearned • u/sundvl13 • 5h ago

TIL the oldest known physical flag in the world is the Derafsh-e-Shahdad (or Standard of Shahdad), it is a bronze flag with a simurgh (mythical bird) dating back to 2,400 B.C.

en.wikipedia.org

409 Upvotes

5 comments

r/todayilearned • u/Gr8fulFox • 4h ago

TIL The reason the word "nine" is said as "niner" over a radio is so that it won't be mistaken as a German "nein"/no.

en.wikipedia.org

4.3k Upvotes

275 comments

r/todayilearned • u/A_W_Z_2 • 6h ago

TIL failed Operation Kiebitz, during WW2 Nazis planned to rescue 4 skilled U-Boat commanders held in Canada POWs camp with a U-Boat, canadians became aware of the plan and laid trap to capture the U-Boat.

en.wikipedia.org

1.1k Upvotes

43 comments

r/todayilearned • u/OccludedFug • 8h ago

TIL that the pink plastic flamingo is the official bird of Madison Wisconsin.

en.wikipedia.org

709 Upvotes

23 comments

r/todayilearned • u/RedditIsAGranfaloon • 10h ago

TIL in 1948, when Satchel Paige was finally signed to pitch in the Major Leagues, The Sporting News named him Rookie of the Year—at (at least) 42 years old.

mlb.com

813 Upvotes

20 comments

r/todayilearned • u/beasterne7 • 10h ago

TIL in crowd wisdom, the 'surprisingly popular' answer can overcome ignorance of the masses

princeton.edu

3.7k Upvotes

144 comments

r/todayilearned • u/TheVentiLebowski • 10h ago

Flavoring, not flavor TIL Ambergris Was an Ice Cream Flavor in the 17th Century

tastingtable.com

3.3k Upvotes

179 comments

r/todayilearned • u/Neebez • 13h ago

TIL a finance worker at a multinational firm was tricked into transferring $25 million to scammers after joining a video conference call where every single other participant—including the company's CFO and several of his recognized coworkers—was an AI-generated deepfake.

cnn.com

22.8k Upvotes

616 comments

r/todayilearned • u/QueenOfNZ • 16h ago

TIL that in 2022, a 7-year-old boy, his brother, and their cousin discovered a rare juvenile T. rex fossil in North Dakota. Dubbed "Teen Rex," it is one of only four juvenile T. rex fossils ever found.

cbsnews.com

5.9k Upvotes

42 comments

r/todayilearned • u/Double-decker_trams • 13h ago

TIL in Medieval England, a form of football (also called mob football) was played between neighbouring villages/towns. Team sizes were unlimited. The teams had to move an item (for example an animal's bladder) to a particular geographical point, such as their opponents' church.

en.wikipedia.org

1.7k Upvotes

93 comments

r/todayilearned • u/AssassinSnail33 • 1h ago

TIL that the two longest rivers located entirely within the Canadian province of Ontario (the Albany River and the Severn River) are exactly the same length. Both rivers are 982 km long, or 610 miles.

en.wikipedia.org

• Upvotes

7 comments

r/todayilearned • u/Sebastianlim • 1d ago

TIL that in 2020, Justin Montney lost his fiancée, Alexis-Athena Wyatt, in a car crash. When he attempted to get a refund from the photography company he had hired for their wedding, they not only refused but released a statement mocking him.

people.com

26.0k Upvotes

925 comments

r/todayilearned • u/carboncopy95437 • 38m ago

TIL In 2002 the pharmaceutical heiress Ruth Lilly gave $200 million to the publisher of Poetry magazine. The gift led to the establishment of the Poetry Foundation in 2003.

en.wikipedia.org

• Upvotes

5 comments

r/todayilearned • u/gelatomancer • 15h ago

TIL Sea Otter Skeletons Can Turn Purple If They Eat Enough Purple Sea Urchins

popsci.com

1.4k Upvotes

29 comments

r/todayilearned • u/RainyWanderlust • 1d ago

TIL about the “blob” slime mould. It has almost 720 sexes, can heal itself, and has no brain, but is able to transmit knowledge if merged with another blob.

abc.net.au

14.4k Upvotes

724 comments

r/todayilearned • u/thebigchil73 • 1d ago

TIL that the ‘high’ from gambling isn’t connected to winning - the dopamine rush peaks at exactly 50:50 probability. Gamblers get a rush when the roulette wheel is spinning but their pleasure is largely unaffected whether they win or lose.

pubmed.ncbi.nlm.nih.gov

8.6k Upvotes

406 comments

r/todayilearned • u/softpetalwishxx • 27m ago

TIL that cows do not have any upper front teeth. Instead, they have a thick, leathery layer of tissue called a "dental pad" which they press their lower incisors against to tear grass.

vivo.colostate.edu

• Upvotes

2 comments

r/todayilearned • u/kevlarbuns • 1d ago

TIL member of the Donner Party, Lewis Keseberg, was accused of killing and consuming multiple, including children, by the rescue party. He was found with the corpse of Tamsen Donner, and had hidden her remaining money. He later sued for defamation, insisting he only ate those who died of exposure.

en.wikipedia.org

8.5k Upvotes

500 comments

r/todayilearned • u/PeasantLich • 1d ago

TIL that Checkers has been a solved game for almost 20 years. Optimal play is unbeatable, and two opponents playing optimally always reach a stalemate.

researchgate.net

31.9k Upvotes

1.4k comments

r/todayilearned • u/Recent_Flounder6011 • 1d ago

TIL that before the Black Death in Europe, there was the Plague of Justinian. The plague weakened the Byzantine Empire's economy and caused the empire's decline.

en.wikipedia.org

1.6k Upvotes

87 comments

r/todayilearned • u/Skaterose6 • 1d ago

TIL Kansas City Chiefs quarterback Patrick Mahomes has a well-known game-day superstition where he wears the same pair of red underwear for every game of his NFL career.

espn.com

2.6k Upvotes

279 comments

r/todayilearned • u/LakeM0bius_hunter • 15h ago

TIL that the Moon moves about 3.8 centimetres farther away from Earth every year.

science.nasa.gov

162 Upvotes

55 comments

Subreddit

Posts

Wiki

Today I Learned (TIL)

r/todayilearned

You learn something new every day; what did you learn today? Submit interesting and specific facts about something that you just found out here.

Members Active

41.7m

Sidebar

New to reddit? Click here!

You learn something new every day; what did you learn today?
Submit interesting and specific facts that you just found out (not broad information you looked up, TodayILearned is not /r/wikipedia).

Posting rules

Submissions must be verifiable. Please link directly to a reliable source that supports every claim in your post title. Images alone do not count as valid references. Videos are fine so long as they come from reputable sources (e.g. BBC, Discovery, etc).
No personal opinions, anecdotes or subjective statements (e.g "TIL xyz is a great movie").
No recent sources. Any sources (blog, article, press release, video, etc.) with a publication date more recent than two months are not allowed.
No politics, soapboxing, or agenda based submissions. This includes (but is not limited to) submissions related to:
1. Recent political issues and politicians
2. Social and economic issues (including race/religion/gender)
3. Environmental issues
4. Police misconduct
No misleading claims. Posts that omit essential information, or present unrelated facts in a way that suggest a connection will be removed.
Rephrase your post title if the following are not met:
1. Titles must begin with "TIL ..."
2. Make them descriptive, concise and specific (e.g. not "TIL something interesting about bacon").
3. Titles must be able to stand on their own without requiring readers to click on a link. Starting your title with a why/what/who/where/how modifier should be unnecessary.
4. "TIL about ..." and other broad posts don't belong on TIL. Try /r/Wikipedia, etc. instead, or be more specific (and avoid the word "about").
5. "TIL how to ..." posts belong on /r/HowTo.
6. "TIL the definition of a word..." Word definitions/translations/origins are not appropriate here
No submissions related to the usage, existence or features of specific software/websites (e.g. "TIL you can click on widgets in WidgetMaker 1.22").
All NSFW links must be tagged (including comments).

Please see the wiki for more detailed explanations of the rules, as well as additional rules that may not be listed here

(Why we need rules)

Additional info

If your post does not appear in the new queue and you think it meets the above rules, please contact the moderators (include a link to your reddit.com post, not your story).
Please report spam, inaccurate or otherwise inappropriate posts by messaging the moderators, as this helps us remove them more promptly!
More information available on the TIL FAQ and wiki.

Frequent TILs Repost List

As of May 2026

This list was compiled from /r/todayilearned community suggestions by its members. If your TIL is found on this list, it will be removed. The titles have been abridged for the sake of brevity, however the context remains the same. This list is subject to change. The purpose is to keep content fresh on /r/todayilearned as requested by its members. If you are interested in reading about the TILs on this list use the search box feature and enter the keywords to pull up past TILs.

Etiquette

We ask that you please do the following:

avoid mobile versions of websites (e.g. m.wikipedia.org)
link to the appropriate heading when referencing an article (particularly on Wikipedia)
link to the appropriate start time when referencing videos (e.g. on YouTube)
add [PDF] or [NSFW] tags to your posts, as necessary.
Please avoid reposting TILs that have already made the front page in the past

Please also read the site-wide Reddiquette.

You are loved.