Casual Speech: 반말
Learn how to speak casually with friends using 반말 (informal speech).
반말 (casual speech, literally 'half-speech') is the intimate register used between close friends, family members of similar generation, and from older speakers to clearly younger ones in established relationships. The transformation is mechanical: drop the polite -요 from -아요/어요 endings. 어디 가요? becomes 어디 가? 좋아요 becomes 좋아.
The social dimension is critical: do not switch to 반말 with anyone you have just met, regardless of their apparent age. Native Korean speakers establish 반말 relationships through explicit social negotiation — typically the older or higher-status person initiates the switch by asking 우리 말 놓을까요? (shall we drop the polite form?). As a foreign speaker, you should almost always stay in 해요체 unless explicitly invited to use 반말. Using 반말 with a stranger can sound aggressive or childish; using 해요체 with a close friend who's invited 반말 can feel cold but is rarely seen as rude.
해요체 → 반말 Conversion
Simply drop 요 from 해요체. 먹어요 → 먹어, 가요 → 가, 했어요 → 했어, 좋아요 → 좋아. For ~ㄹ게요 → ~ㄹ게, ~ㄹ까요? → ~ㄹ까?
~자 — Let's (casual suggestion)
Verb stem + 자 = 'Let's ~' in casual speech. 가다 → 가자 (let's go), 먹다 → 먹자 (let's eat), 하다 → 하자 (let's do it). This is the 반말 equivalent of ~(으)ㄹ까요?
How It Works
반말 is mechanically the easiest thing in this level: take 해요체 and drop the 요. 먹어요 becomes 먹어, 갔어요 becomes 갔어, 좋아요 becomes 좋아. The endings you have already learned convert directly.
A few forms change slightly rather than just shortening. -(으)ㄹ게요 becomes -(으)ㄹ게, -(으)ㄹ까요? becomes -(으)ㄹ까?, and the copula 이에요/예요 becomes 이야/야: 학생이야, 민지야.
-자 is the casual propositive, replacing -(으)ㄹ까요? when suggesting something to a friend. 가자, 먹자, 하자. It attaches straight to the stem with no vowel rule, which makes it one of the simplest endings in Korean.
The difficulty of 반말 is entirely social rather than grammatical. Using it with the wrong person is a genuine breach, not a minor stylistic slip. It is appropriate with close friends of the same age, with people clearly younger who have accepted it, and within families. It is not appropriate with strangers, colleagues you are not close to, or anyone older, regardless of how friendly the conversation feels.
The transition is usually explicit. Someone will say 말 놓자 or 말 편하게 해 ('let's drop the formality'), and that invitation normally comes from the older or senior person.
Where You'll Hear It
반말 is what you hear in dramas, variety shows and music, which is why learners often absorb it passively long before they are in a position to use it. Recognising it is therefore genuinely useful even if you never produce it.
It is also how people talk to children and pets, and how close friends talk among themselves. Overhearing a group of friends will give you a much more natural model of Korean sentence rhythm than textbook dialogue does.
The invitation to switch is a real social moment. Accepting 말 놓자 marks a shift in the relationship, and continuing with 해요체 afterwards reads as keeping distance. Conversely, switching without being invited is presumptuous in a way that is hard to recover from.
-자 appears constantly in casual plans: 밥 먹자, 나중에 보자, 이따 연락하자. If you have Korean friends your own age, these are among the first things you will both say and hear.
One asymmetry worth knowing: in a mixed-age group, the younger person may use 존댓말 while the older uses 반말, and this is normal rather than rude. Korean relationships are frequently non-reciprocal in register.
Cultural & Language Note
반말 is not simply casual — switching to it without permission is a social move. Koreans often negotiate it explicitly with 말 놓을까요? ('shall we drop the formality?'), and the older or higher-status person initiates. Using 반말 with someone who has not agreed to it reads as presumptuous in a way that has no direct English equivalent.
Common Mistakes to Avoid
Converting 해요체 to 반말 is mostly a matter of dropping 요, but the copula is irregular: 학생이에요 becomes 학생이야, not 학생이에. Learners also use 반말 with service staff who are younger, which is not acceptable — age alone does not license it outside of established relationships.
How to Practice This Lesson
Prioritise recognition over production. You will hear 반말 in every drama and song you encounter, and being able to parse it doubles the amount of Korean media you can follow. Practise converting 반말 you hear back into 해요체 to confirm you have understood the underlying form.
Drill the conversion in both directions with ten sentences, paying attention to the forms that change rather than just shorten: 이에요 → 이야, -(으)ㄹ게요 → -(으)ㄹ게.
For production, wait. The safest default as a learner is to stay in 해요체 until someone explicitly invites you to switch. Nobody will be offended by 해요체; plenty of people would be by unsolicited 반말.
If you do have a same-age Korean friend, ask directly whether you can use 반말 with each other. Asking is entirely normal and removes the guesswork, and Koreans generally appreciate that a learner understands the distinction well enough to ask.