Which Korean speech level should I use?
Korean encodes the relationship between speaker and listener in the verb ending. 해요 is the everyday polite form and the safe default for a learner. 합니다 is formal and used in broadcasting, presentations and the military. 반말 is casual and used only with close friends, people clearly younger, or after someone has invited you to use it.
The three you actually need
Korean has more levels historically, but three cover essentially all modern use. Learners should start with 해요 and add the others as the situations arise.
가요
gayo
I go / go.
해요 — polite, everyday.
갑니다
gamnida
I go.
합니다 — formal.
가
ga
I go.
반말 — casual.
Level marks the relationship, not the topic
The same sentence takes a different ending depending on who you are speaking to, and switching level mid-conversation signals that something about the relationship has changed. In drama this is used deliberately as a plot beat.
밥 먹었어요?
bap meogeosseoyo?
Have you eaten?
To a colleague or someone older.
밥 먹었어?
bap meogeosseo?
Have you eaten?
To a close friend.
Dropping to 반말 is a negotiated step
You do not switch to casual speech because you feel comfortable. It is normally proposed — 말 놓을까요, shall we drop the formality — and accepted. Doing it unilaterally with someone older or senior is a genuine social error rather than a grammatical one.
말 놓을까요?
mal noeulkkayo?
Shall we speak casually?
편하게 말씀하세요.
pyeonhage malsseumhaseyo
Please speak comfortably.
An invitation to relax the level.
Common mistakes
Using 반말 with someone you have just met.
Use 해요 until invited otherwise.
Casual speech with a stranger or someone senior reads as rude rather than friendly, and the offence is real even if unintended.
Using 합니다 with friends.
해요 or 반말.
Formal endings among friends sound cold or sarcastic — over-politeness is also a mismatch.
Copying drama 반말 directly into conversation.
Match the level to your actual relationship.
Drama characters are usually close friends or family. Their register does not transfer to your situation.
Frequently asked questions
Which level should a beginner learn first?
해요. It is polite enough for nearly every situation a learner will be in, it is what textbooks teach first, and no one will be offended by it. Add 합니다 for formal settings and 반말 only once someone has offered.
Is age really what decides it?
Age is the most visible factor, but the real variables are relative status, closeness and setting. A younger boss still receives polite speech, and Korean commonly establishes age early precisely to settle which level applies.
What is 하십시오체 and do I need it?
It is the most formal level, used in announcements, signage and the military. You need to recognise it, but you will rarely produce it outside a scripted setting.