Retrocodex: Stuff You Learned Wrong is a collection of commonly taught facts that aren't actually true.
Browse and discuss 100+ commonly taught disproven, outdated facts with sources. Follow other users from your same state or country to see what teachers and parents from your region got wrong growing up.
This website was inspired by a viral social media post that's been going around since 2020.
Thousands of social media users asked for it, so we knew it
had to exist. We combed through every comment figuring out how
to make it as inclusive of a massive range of global learning
experiences as possible.
So far, we're doing it through having
users optionally show off what state or country they're from
so other folks sharing that can find what their region got
wrong. Make an account anytime to see a local feed of what users from your state or country have had to unlearn.
We don't know exactly what everyone around the world was taught growing up. We only know what was commonly taught around the world and what our users submit.
Looking up every school district's curriculum only tells us what your schools were supposed to teach you, not what they actually taught. Aside from facts you were taught in school that have since been disproven, it also includes urban legends and old wives' tales your parents may have passed down.
Retrocodex is NOT a political or news media fact-checker.
This site is NOT a political fact-checker to discuss current political events or news media. If that's what you're looking for, please visit Politifact, FactCheck.org, or VietFactCheck.
However, it does feature topics that may be inadvertently politicized by the public, such as false or contested scientific and historical claims used to support current political agendas and contemporary media claims.
Retrocodex does platform a few facts about socially controversial, marginalized identities such as non-binary and transgender individuals based on solid historical records rather than bipartisan advocacy. These facts are intended to correct or prevent common societal misconceptions of each group.
You may see some examples of disproven or debated facts used to support factually misleading contemporary media claims, such as "Americans don't eat enough protein" or "We have definitely achieved artificial general intelligence in 2026."
What's true today may not always be true tomorrow.
New evidence behind each disproven fact can turn up anytime. For example, a new Food Pyramid was released in January 2026 while this website was being developed. If you spot any factual information that later evolved since we posted it, tell us in the entry's comment section.
Retrocodex is running in beta mode.
Sadly, we're burning through quite a few pricey services to keep the site running, so we're currently seeking donations! Retrocodex was created by retro_christina.