Korean Dictionary
How to say "I don't know" in Korean
“I don't know” in Korean is 모르겠어요 (pronounced "Moreugesseoyo").
모르겠어요
Moreugesseoyo
Usage & Context
A very useful phrase when you are lost or confused. Adding '잘' before it ('잘 모르겠어요') softens the expression and sounds more natural.
Example Sentence
죄송해요, 잘 모르겠어요.
Sorry, I don't know.
How to use 모르겠어요 naturally
Quick answer
The Korean word for “I don't know” is 모르겠어요, romanized as Moreugesseoyo.
Usage tip
Learn this word together with a complete Korean sentence. Meaning often depends on particles, politeness level, and word order.
Common mistake
Do not rely only on the English meaning. Read the Korean example sentence and notice the particles, word order, and politeness level around 모르겠어요.
Pronunciation Guide
Pronounced 'mo-reu-ge-sseo-yo' — 'mo' is a quick 'moh,' 'reu' is a soft 'ruh,' 'ge' rhymes with 'geh,' and 'sseoyo' ends softly.
Formal & Casual Forms
Formal (존댓말)
모르겠습니다
moreugesseumnida
Formal, used in business or with strangers
Casual (반말)
몰라
molla
Casual, used with close friends — also a playful/dismissive 'dunno'
More Example Sentences
trying to recall a name
그 사람 이름을 잘 모르겠어요.
I don't really know that person's name.
puzzling over a Korean word
이게 무슨 뜻인지 모르겠어요.
I don't know what this means.
hedging on a question
글쎄요, 잘 모르겠어요.
Well, I'm not really sure.
Cultural Context
Koreans soften statements with 모르겠어요 ('I don't know') even when they do have an opinion — it's a polite way to avoid confrontation or commit. 몰라 between friends can sound cute, pouty, or dismissive depending on tone. The form 잘 모르겠어요 ('I don't really know') is especially soft and polite.
Editorial note
We review entries like 모르겠어요 for pronunciation, example sentence fit, and learner mistakes so the page answers more than a direct dictionary lookup.
Reviewed by Min-jung Park, Korean Language Teacher. Updated May 31, 2026. See our editorial standards.
Common Phrases
모르겠어요.
I don't know.
잘 모르겠어요.
I'm not really sure.
몰라요.
I don't know. (polite)
Related Expressions
알다
alda
to know (antonym)
글쎄요
geulsseyo
well... / not sure
잘 모르겠어요
jal moreugesseoyo
I don't really know
몰랐어요
mollasseoyo
I didn't know
기억 안 나요
gieok an nayo
I don't remember
More Expressions Words
Related Guides
Korean Text Slang Guide
The most common Korean text slang is "ㅋㅋㅋ" (kkk), which represents laughter like "hahaha" in English. Other essential slang includes "ㅎㅎ" (hh, soft laughter), "ㅇㅇ" (oo, meaning yes/okay), and "ㄴㄴ" (nn, meaning no). Korean text slang heavily uses consonant abbreviations from Hangul.
K-Drama Phrases You Should Know
The most iconic K-drama phrase is "가지 마" (gaji ma), meaning "Don't go" — used in countless dramatic separation scenes. Other essential K-drama phrases include "미쳤어?" (michyeosseo? — Are you crazy?), "어떡해" (eotteokae — What do I do?), and "진짜?" (jinjja? — Really?).
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