Studying vocabulary in bulk is easy to start and easy to abandon. Today’s Four-Character Idiom Quiz takes the opposite approach: one question a day, the same question for everyone, built around Korean’s four-character idioms known as sajaseongeo. Instead of grinding through a hundred flashcards, you get one shot at one idiom, and a full day to sit with it.
I built this because I kept forgetting the sajaseongeo I had crammed the night before a test, back in school. Cramming a list never stuck, but the handful of idioms I actually remembered years later were the ones tied to a specific moment of getting them wrong in front of someone. So instead of another flashcard deck, I designed an app around that one moment: a single question, a real chance to be wrong, and a card that explains why.
Features
- One shared question a day: a new idiom unlocks at midnight Korea time, and everyone solving the quiz that day gets the same one
- Fill-in-the-blank with consonant hints: guess the missing character out of the four, with up to three attempts and an optional hint if you get stuck
- A learning card either way: right or wrong, you unlock a card with the idiom’s meaning, the reading and meaning of each character, its origin story, and example usage
- Spaced review: solved idioms resurface after 1, 3, and 7 days, and your full history stays available to revisit anytime
- Streaks and stats: track your current streak, accuracy, attempt distribution, and a 12-week activity grid of your study history
- Spoiler-free sharing: share the blank-filled question, the meaning, and your own result without giving away the answer to friends who haven’t solved it yet
- Daily reminders: an optional notification at a time you choose, toggled on or off from settings
Every idiom is checked against the Standard Korean Language Dictionary and Urimalsaem, Korea’s two major reference dictionaries. The question set is built not to repeat for roughly three years, and there’s no account to create — you can start right on your device.
This is a Korean-language app at heart, and I’m not going to pretend otherwise. It’s for people studying Korean seriously enough to want sajaseongeo specifically, native Korean speakers who want to sharpen idioms they half-remember from school, and anyone in the Korean diaspora looking for a small daily link back to the language. If any of that sounds like you, one question a day is a low bar to clear and a decent reason to open the app before bed.
Today’s Four-Character Idiom Quiz, originally named 오늘의 사자성어 in Korean, is live now on the App Store. Grab it, wait for midnight, and see if you know today’s idiom.
