Aspiration in Korean: Lessons and Practice

Key Facts

• ㅎ + ㄱ ㄷ ㅈ becomes ㅋ ㅌ ㅊ: 좋다 is [조타].
• ㄱ ㄷ ㅂ ㅈ + ㅎ becomes ㅋ ㅌ ㅍ ㅊ: 입학 is [이팍].
• ㅎ + ㅅ gives a tense sound: 닿소 is [다쏘].
• The double finals ㄶ and ㅀ also aspirate and keep ㄴ or ㄹ: 많다 is [만타].
• The rule is in Article 12 of the Standard Pronunciation Rules (표준 발음법).
• Three lessons cover the overview and each direction, with audio.

Last updated: 2026-10-09. The Korean text, romanization and audio scripts in this section were generated and reviewed and signed off by Min-ji Park on 15 October 2026.

What Is the Korean Aspiration Rule?

The Korean aspiration rule is a sound change that merges ㅎ with a neighbouring stop into one aspirated stop. An aspirated consonant is a stop released with a strong puff of air. Korean has three kinds of stop: plain (ㄱ ㄷ ㅂ ㅈ), tense (ㄲ ㄸ ㅃ ㅉ) and aspirated (ㅋ ㅌ ㅍ ㅊ). The letter ㅎ is a breath sound, so when it joins a plain stop it adds the breath.

The result is one sound, not two. Nobody says ㅎ and then ㄷ in 좋다. They say a single ㅌ, and the first block ends in a vowel. The rule works in two directions, and the table shows both.

Revised Romanization (RR) writes the aspirated result for verbs and adjectives, so 좋다 is jota, but for nouns it keeps the spelling, so 입학 is iphak and 축하 is chukha. RR is a learning aid on this site, and the Hangul and the bracketed forms are the reference. The next table sends each learner to the right lesson.

Where to Start with the Korean Aspiration Rule

Start with the lesson that matches the word you want to say. The table gives one starting point for each situation.

A learner who knows the overview can take the two direction lessons in either order. A beginner should take them in the order below, because the ㅎ-first words 좋다 and 많다 appear earliest in beginner vocabulary. The first lesson is the overview.

What Is the Rule?

The rule is that ㅎ and a plain stop become the matching aspirated stop, whichever comes first. The lesson Korean Aspiration Rules puts both directions in one table, and it shows the fusion as a diagram so that the result reads as one sound.

The pairs are one-to-one: ㄱ gives ㅋ, ㄷ gives ㅌ, ㅂ gives ㅍ and ㅈ gives ㅊ. The lesson also covers the learner question that comes first in practice: why 어떻게 is said [어떠케]. The two direction lessons then take each half in detail.

What Happens When ㅎ Comes First?

When ㅎ comes first, a final ㅎ merges with a following ㄱ, ㄷ or ㅈ. The lesson Korean ㅎ Aspiration teaches 좋다 [조타], 놓고 [노코], 좋지 [조치], 많다 [만타], 싫지 [실치] and 닿소 [다쏘].

Two details make this lesson more than a single rule. The double finals ㄶ and ㅀ keep their ㄴ or ㄹ and aspirate the next consonant, so 많다 keeps the ㄴ: [만타]. And ㅎ followed by ㅅ gives a tense sound, so 닿소 is [다쏘]. A final ㅎ before a vowel does something different, which is silence, and that case belongs to the ㅎ weakening and deletion section.

What Happens When ㅎ Comes Second?

When ㅎ comes second, a final ㄱ, ㄷ, ㅂ or ㅈ merges with the ㅎ that begins the next block. The lesson Korean Aspiration Before ㅎ teaches 입학 [이팍], 축하 [추카], 맏형 [마텽], 앉히다 [안치다] and 먹히다 [머키다].

This direction matters because it appears in two kinds of word that learners meet early: Sino-Korean school and celebration words such as 입학 and 축하, and the passive and causative forms with the suffix -히-, such as 먹히다. The lesson also contrasts 입학 [이팍] with 입이 [이비], where a vowel follows instead of ㅎ. The table below compares all three lessons.

Comparing the Korean Aspiration Rule Lessons

The table compares the lessons by what each one fixes, its level and its length.

Each lesson uses everyday vocabulary as its headline examples, so the first audio is useful straight away. The next question is how to practise between lessons.

How Do You Practise the Korean Aspiration Rule?

Practise by locating ㅎ first, then asking which side of it the stop is on. Use this routine.

1. Read 좋다 and 놓고 and say ㅎ + stop as one puff: [조타], [노코].
2. Read 입학 and 축하 and say stop + ㅎ as one puff: [이팍], [추카].
3. Hold a hand in front of your mouth. A strong puff of air should land on the ㅌ, ㅋ or ㅍ.
4. Say 많다 [만타] and 앉히다 [안치다], and keep the ㄴ.

The rule also works across a space when two words are said together: 꽃 한 송이 (one flower) is [꼬탄송이], because final ㅊ is first said as [ㄷ] and then joins the ㅎ of 한.

Test yourself on ten cases. Cover the right-hand column, say each word, then check.

Every answer except 닿소 has an aspirated ㅋ, ㅌ, ㅍ or ㅊ; 닿소 has the tense ㅆ instead.

For contrast training between plain, tense and aspirated sounds, use the plain, tense and aspirated minimal pairs. The overview of all rules is in Korean pronunciation rules.

Study Order at a Glance

Take the overview first, then ㅎ first, then ㅎ second. The ㅎ-first lesson comes before the ㅎ-second lesson because 좋다 and 많다 are among the first adjectives a learner meets, while the ㅎ-second lesson adds the -히- forms that belong to later grammar. After the third lesson, Korean palatalization is the natural next step.

What Does This Section Cover, and What Does It Leave Out?

The section covers the merging of ㅎ with ㄱ ㄷ ㅂ ㅈ in standard Seoul-based pronunciation. It does not cover ㅎ before a vowel, where the ㅎ is silent, and it does not cover regional variants. The Korean examples and audio were machine-generated and reviewed and signed off by Min-ji Park on 15 October 2026.

Frequently Asked Questions

What is aspiration in Korean sound changes? Aspiration (격음화) is the sound change in which ㅎ and a plain stop (ㄱ, ㄷ, ㅂ or ㅈ) fuse into one aspirated stop (ㅋ, ㅌ, ㅍ or ㅊ). It works in both orders, so 좋다 is said [조타] and 입학 is said [이팍]. The spelling does not change.

Why is 좋다 pronounced 조타? The final ㅎ of 좋 meets the ㄷ of 다. Korean joins them into one aspirated ㅌ, so the first block ends in a vowel and the second block starts with a breathy t. The same pattern gives 놓고 [노코] and 좋지 [조치].

Does 어떻게 follow the aspiration rule? Yes. The final ㅎ of 어떻 meets the ㄱ of 게, and the two join into ㅋ, so the word is said [어떠케]. It is one of the most common aspiration words, and it follows exactly the same pattern as 놓고 [노코].

Is aspiration shown in Revised Romanization? Only partly. Revised Romanization writes the aspirated result in verbs and adjectives, so 좋다 is jota. In nouns it keeps the spelling, so 입학 is iphak and 축하 is chukha, which hide the aspirated sound. Because RR is inconsistent here, the Hangul and the bracketed spoken form are the reference.

Where to Go Next

To see every sound change in one place, return to Korean pronunciation rules. To continue, open Korean Aspiration Rules, which starts the Korean aspiration rule lessons.