Side by side
안 vs 지 않다: Two Ways to Say 'Not'
Same meaning, different register, plus one placement rule that catches everybody.
Korean gives you two ways to negate a verb, and unlike most particle pairs, they genuinely mean the same thing. 안 먹어요 and 먹지 않아요 both mean "I don't eat".
So the choice is about register and rhythm, not meaning. But there is one placement rule with 하다 verbs that trips up nearly every learner, and a small group of verbs that reject both forms entirely.
In one line
안 is the short, spoken negation placed before the verb. 지 않다 is the longer, more formal ending attached to the stem.
| Particle | Core meaning | Used with | Example |
|---|---|---|---|
| 안 (an) | Not (short form) | Everyday speech, short sentences | 안 먹어요 an meogeoyo I don't eat |
| 지 않다 (ji anta) | Not (long form) | Writing, formal speech, emphasis | 먹지 않아요 meokji anayo I do not eat |
When to Use 안
1. Everyday Conversation
안 is what you will hear most in daily speech. It goes directly before the verb or adjective, as a separate word.
오늘은 안 바빠요.
oneureun an bappayo.
I'm not busy today.
2. Split 하다 Verbs
With noun + 하다 verbs, 안 goes between the noun and 하다, not in front of the whole word. This is the single most common negation mistake.
공부 안 해요.
gongbu an haeyo.
I don't study.
3. Quick Answers
For short replies and casual denials, 안 is far more natural than the long form, which would sound stiff.
아니요, 안 갔어요.
aniyo, an gasseoyo.
No, I didn't go.
When to Use 지 않다
Attach 지 않다 to the verb stem. It is the default in writing, news, formal announcements, and academic text, and it also gives a little extra weight in speech, useful when you want the negation to land firmly rather than in passing. With long or compound verbs it often reads more smoothly than 안.
그렇게 생각하지 않습니다.
geureoke saenggakaji anseumnida.
I do not think so.
잘 이해되지 않아요.
jal ihaedoeji anayo.
It's hard to understand.
쉽지 않아요.
swipji anayo.
It isn't easy.
The core difference
How people talk
“Short and quick”
How people write
“Formal and firm”
Common mistakes
안 공부해요
an gongbuhaeyo
공부 안 해요
gongbu an haeyo
With noun + 하다 verbs, 안 splits the word. The same applies to 일 안 해요, 운동 안 해요, 요리 안 해요.
안 알아요
an arayo
몰라요
mollayo
알다 (to know) has its own negative verb, 모르다. Neither 안 nor 지 않다 works with it.
안 있어요
an isseoyo
없어요
eopseoyo
있다 (to exist / have) also has a dedicated opposite: 없다. Never negate it with 안.
먹지 않 해요
meokji an haeyo
먹지 않아요
meokji anayo
지 않다 is one unit and conjugates on 않다 itself. Do not insert 하다.
안 먹어요 / 못 먹어요
an meogeoyo / mot meogeoyo
Both correct, different meanings
안 means you choose not to. 못 means you are unable to. 안 먹어요 is 'I don't eat it'; 못 먹어요 is 'I can't eat it'.
How to Choose in 5 Seconds
Ask these in order and stop at the first yes.
Frequently asked questions
Is there any meaning difference at all?
Not in the core meaning. The difference is register and emphasis: 안 is shorter and more conversational, 지 않다 is more formal and lands with slightly more weight.
Why does 안 go inside 공부하다?
Because 공부하다 is really the noun 공부 plus the verb 하다. 안 negates the verb part, so it slots in right before 하다: 공부 안 해요.
Which verbs cannot use 안?
알다 → 모르다 and 있다 → 없다 have dedicated negative forms, and 안 알아요 or 안 있어요 sounds wrong. 맛있다 has 맛없다 as its usual opposite, though 안 맛있어요 is common in casual speech.
Can I use 안 with adjectives?
Yes. 안 예뻐요 and 예쁘지 않아요 are both correct and mean the same thing. The same register rule applies.
What about 못?
못 is a third option meaning 'cannot': inability rather than choice. It has its own long form, 지 못하다, which follows the same formal/casual split.
Look them up in the dictionary
Both particles in the Basic Korean Dictionary from the National Institute of Korean Language, with English.