How to Say “I Don’t Know” in Korean: 몰라 (molla)

“Molla” means “I don’t know” — a casual shrug of an answer for friends.

몰라 (molla) — I don’t know

How it feels and when to use it

Softer and more common is “moreugesseo” (모르겠어, “I’m not sure”), which sounds less blunt. Bare “molla!” can be playful or dismissive depending on tone.

Politeness levels

몰라 (molla) — Casual (반말): with close friends and people younger than you
몰라요 (mollayo) — Polite (해요체): the safe everyday level for most people
모르겠습니다 (moreugesseumnida) — Formal (합쇼체): in business, announcements, and to elders

Real examples from native Korean

Here’s how native speakers actually use 몰라 in real Korean:

나 룰을 몰라 — I do not know the rules.
잘 몰라. 이거. — I do not know. this.
나 뭔지 몰라서. — I don't know what it is.

A common mistake to avoid

Use “moreugesseo” to be polite — A flat “mollayo” to a teacher or stranger can feel curt or evasive. “Moreugesseoyo” (I’m not sure) is the softer, more respectful “I don’t know.”

Related expressions

알았어 (arasseo) — got it
글쎄 (geulsse) — well, hmm / not sure

Want to hear 몰라 spoken by real Koreans? Search it on Langle and watch it across dozens of real video clips.

Frequently asked questions

What does “몰라” mean in Korean?

“Molla” means “I don’t know” — a casual shrug of an answer for friends. It’s romanized as “molla.”

Is “몰라” formal or casual?

“몰라” is casual (반말); “몰라요” is polite (해요체); “모르겠습니다” is formal (합쇼체). Match the level to who you’re talking to.

How do you pronounce “몰라”?

It’s pronounced “molla.” Use “moreugesseo” to be polite: A flat “mollayo” to a teacher or stranger can feel curt or evasive. “Moreugesseoyo” (I’m not sure) is the softer, more respectful “I don’t know.”

When should I use “몰라”?

Softer and more common is “moreugesseo” (모르겠어, “I’m not sure”), which sounds less blunt. Bare “molla!” can be playful or dismissive depending on tone.

What can I say instead of “몰라”?

Try “알았어” (got it) or “글쎄” (well, hmm / not sure).