localize-ko

Korean Translation Rules (ko / 한국어)

Distilled from the production translation prompts. Follow these rules verbatim — they are model-agnostic and produce consistent native-quality Korean output.

Mindset

As a native Korean writer, you strongly dislike literal English translations and unnatural Korean expressions.

You are a strict Korean native writer who rejects English-style direct translation and Konglish. Preserve meaning, restructure ALL English SVO into SOV, and prefer native Korean over transliterated English when both exist.

Pre-Translation Setup

Lock in before translating:

Speech level (존댓말) — Default to 해요체 (Polite) for modern UI, or 하십시오체 (Formal) for official docs. NEVER use 해체 (Casual) in professional contexts. Never mix levels.
SOV word order — Restructure all English SVO sentences.
Pro-drop language — Omit 당신/너/저 when context is clear.
Half-width punctuation — Korean uses ASCII punctuation (unlike Japanese/Chinese).
Placeholders — Preserve {variables} and ICU plural syntax exactly.

Register Auto-Detection (run after Pre-Translation Setup, before translating)

If the user has NOT explicitly specified the speech level, infer it from the source text register. Match the output to the source — formal source → 하십시오체, informal source → 해요체. NEVER use 해체 (casual) regardless of source informality — it is forbidden in professional UI.

Formal source signals → output 하십시오체 (-습니다 / -ㅂ니다 / -십시오)

Hedging / polite modals: "please", "kindly", "we recommend", "we kindly request", "could you", "would you mind"
Passive / impersonal: "users are advised", "it is recommended", "applicants must"
No contractions, full sentences, formal connectors
Domain vocabulary: legal, financial, healthcare, regulatory, enterprise B2B, government, insurance
Third-person / distance: "the user must", "customers should"
Brand voice: bank, insurance, government, B2B SaaS, healthcare, legal tech
No exclamations or emojis

Informal source signals → output 해요체 (-어요 / -아요 / -세요)

Contractions: "don't", "you'll", "it's", "we're"
Casual greetings: "hey", "hi there", "yo", "what's up", "hi 👋"
Second-person directness, exclamations, emoji presence (🎉 😎 🚀 ✨)
Slang: "cool", "awesome", "no worries", "kinda"
Consumer-app voice: gaming, social, lifestyle, dating, fitness, kids
Sentence fragments and conversational filler

Mixed / ambiguous source → default to 해요체

Modern Korean software defaults to 해요체 (polite but friendly). 하십시오체 reserved for explicitly formal / government / banking / very B2B.

Explicit user override

If the user says "use formal speech" / "use 하십시오체" / "make it casual" — their instruction wins.

Worked examples

Source	Detected register	Korean output style
"Please review the terms of service before proceeding."	formal	진행하기 전에 이용 약관을 확인하십시오.
"Hey! Tap here to get started — it's super quick 🚀"	informal (해요체)	안녕하세요! 여기를 눌러 시작하세요. 정말 빨라요 🚀
"Submit your application by the deadline."	formal	기한 내에 신청서를 제출하십시오.
"Don't forget to save your work!"	informal (해요체)	작업을 저장하는 것을 잊지 마세요!

After detection: keep the chosen speech level consistent throughout the file. The no-mixing rule still applies.

Critical Accuracy Rules (NEVER violate)

1. Particles by final sound (받침)

Sound	Subject	Object	Topic	And
Ends in consonant (받침 O)	이	을	은	과
Ends in vowel (받침 X)	가	를	는	와

Loanwords / abbreviations — choose particle by KOREAN PRONUNCIATION of the final syllable:

Loanword	Korean reading	Final	Particle
Google	구글	글 (받침 ㄹ)	을 / 이 / 은
API	에이피아이	이 (vowel)	를 / 가 / 는
GPT-5	파이브	브 (vowel ㅡ)	를 / 가 / 는
RTL	알티엘	엘 (받침 ㄹ)	을 / 이 / 은
USB	유에스비	비 (vowel)	를 / 가 / 는

NEVER output both particles like RTL을(를) or 이(가) — that is a mechanical artifact. Always pick exactly one based on pronunciation.

2. Word vs Character — completely different

English	Wrong	Correct
word count	글자 수	단어 수
character count	단어 수	글자 수

word = 단어 ; character = 글자.

3. FOR vs PER — total vs rate

English	Wrong	Correct
for # languages (total)	#언어당	#개 언어에 대해 / #개 언어 기준
per language (rate)	언어에 대해	언어당 / 각 언어마다

4. Measurement unit words after numeric placeholders

Wrong	Correct
{seconds} 후 삭제	{seconds}초 후 삭제
{minutes} 후 재시도	{minutes}분 후 재시도
남은 시간: {hours}	남은 시간: {hours}시간
{days} 이내 완료	{days}일 이내 완료

5. Temporal expression agreement

Meaning	Use	Don't use
Countdown / future	~후 (after)	~중 (means "during")
Ongoing status	~중 / ~하는 중	~후
Deadline	~이내 (within)	—

{days}일 중 is wrong — means "during the daytime". Use {days}일 후.

6. Placeholder type markers

Wrong	Correct
{formatList} 파일 지원	{formatList} 형식의 파일 지원
{languageList} 콘텐츠	{languageList} 언어의 콘텐츠

7. Measure words (분류사)

Counter	Use for
개	General items, languages
명	People
건	Cases / records
가지	Types / kinds
번	Times / counts

Wrong: {count}언어 → Correct: {count}**개** 언어. Wrong: {count}명 언어 → 명 is for people, not items.

Native vs Sino-Korean Numerals

Korean has two number systems, and the wrong system with a counter is immediately wrong to native ears.

Two number systems

#	Native Korean (고유어)	Sino-Korean (한자어)
1	one (one/han)	일
2	둘 (둘/두)	이
3	셋 (셋/세)	삼
4	넷 (넷/네)	사
5	five	오
6	six	육
7	seven	칠
8	eight	팔
9	nine	구
10	열	십
20	twenty (seumu)	isip
30	thirty	samsip
40	forty	sasip
50	쉰	osip
60	sixty	yuksip
70	seventy	chilsip
80	eighty	palsip
90	ninety	gusip
100	백 (Sino-only past 99)	백
1000	—	천
10000	—	만
100000000	—	억

Native numbers stop at 99; from 100 up, Korean uses Sino-Korean.

Use NATIVE numbers with these counters

Counter	Meaning	Example
개	general items	세 개 (3 items)
명	people	five people (5 people)
분	people (honorific)	두 분 (2 people, polite)
살	age in years	twenty years old (20 years old)
시	clock hour	twelve o'clock (12 o'clock)
mari	animals	one animal (1 animal)
권	books	세 권 (3 books)
잔	cups	두 잔 (2 cups)
병	bottles	한 병 (1 bottle)
geureut	bowls	two bowls (2 bowls)

Note attributive forms when modifying a counter: hana → han, dul → du, set → se, net → ne, seumul → seumu. (한 개, NOT 하나 개.)

Use SINO-KOREAN numbers with these counters

Counter	Meaning	Example
분	minutes	thirty minutes (30 minutes)
초	seconds	십 초 (10 seconds)
일	days	오 일 (5 days)
월	months	삼 월 (March)
년	years	year 2024 (year 2024)
번	number / ordinal	일 번 (number 1)
원	won (currency)	five thousand won (5,000 won)
층	floor	오 층 (5th floor)
호	room/number	room 301 (room 301)
차	sequence / nth	일 차 (1st round)
inbun	servings	two servings (2 servings)

Mixed pattern for time

Hour = native, Minute = Sino-Korean: 세 시 삼십 분 (3:30)
오후 두 시 십오 분 (2:15 PM)
In digital UI, prefer numerals + units: 14:30 or 오후 2시 30분 (where 2 reads as du [native] and 30 reads as samsip [Sino]).

Common UI pitfalls

Wrong	Correct
일 개 (1 item)	한 개
삼 명 (3 people)	세 명
두 분 (2 minutes — time)	이 분
five won (5 won)	오 원
한 초 (1 second)	일 초
이 살 (2 years old)	두 살

8. Plural marker 들 — omit when number is present

Wrong: {count}개 파일들 → Correct: {count}개 파일.

9. Domain terminology — use IT loanwords

Source	Wrong (literal)	Correct (IT term)
architecture	architecture	architecture
pipeline (CI/CD)	plumbing	pipeline
deploy	deploy (military)	deploy
source of truth	source of truth	source of information / reference point
bug (software)	worm	bug

UI Conventions

Buttons — verb stem / noun form

Wrong	Correct
create a project	create project
save	save

Status messages — ongoing → ~중

Wrong	Correct
translate	translating / in the process of translating
upload	uploading...

Completion messages — ~complete / ~has been done

Wrong	Correct
save	save complete / has been saved
translate	translation has been completed
uploading (for completed)	upload complete

Empty state — negative existence

Wrong	Correct
the result is empty	no results / results cannot be found
not selected	no items selected

Drag and drop

English	Korean
drag	drag
drop	drop / place
release (let go)	put down / drop — NOT allow (permit)
browse (file picker)	browse / select file — NOT browse

Validation messages

Connectors: and / and (and), or (or), only / only (only).

Wrong: 3-50자, 문자, 숫자, 하이픈만
Correct: 3-50자, 사용 가능: 영문자, 숫자, 하이픈

Other UI patterns

Wrong	Correct	Reason
alternative detection	alternative detection method	Labels need complete noun phrases
automatic (bare)	automatic mode / automatic detection	Add completing noun
25+ languages	more than 25 languages	"N+" → N or more ~
+{count} 더	외 {count}개	"+N more" pattern

Speech Level Consistency

NEVER mix levels in same context.

Don't mix	Use
please change + press	please change + press (polite informal style)
please confirm + saved	please confirm + has been saved (formal polite style)

UI labels (buttons/nouns) stay in stem/noun form regardless of speech level.

Politeness Softeners

Korean has fine-grained politeness markers that soften requests, questions, and statements. Use sparingly — overuse sounds obsequious.

Softening adverbs

Marker	Romanization	Function	Example
좀	jom	"a little" / "please" — conversational softener	`좀 기다려 주세요` (please wait) — softer than `잠시만 기다려 주세요`
please	budi	"kindly" / "please earnestly" — formal	`부디 확인해 주시기 바랍니다` (we kindly request your confirmation)
by any chance	hoksi	"by any chance" — softens questions / hedges	`혹시 시간이 있으신가요?` (do you happen to have time?)
briefly	jamsi	"for a moment" — buffers requests	`잠시만요` (one moment please)
if possible	amujjorok	"in any case" / "above all" — earnest hope	`아무쪼록 양해 부탁드립니다` (we earnestly ask for your understanding)

~주세요 ending (CRITICAL)

The ~주세요 ending is the standard polite request marker in 해요체. Do NOT omit it when making a request — bare imperatives sound rude.

Wrong (bare)	Correct (with 주세요)
check	please check
wait	please wait
enter	please enter

~시- honorific infix (subject elevation)

The ~시~ infix elevates the subject of the verb (the person doing the action). It produces honorific verb stems.

Plain verb	Honorific form	Meaning
가다 (go)	가시다	(someone respected) goes
먹다 (eat)	잡수시다	(someone respected) eats
있다 (be / exist)	계시다	(someone respected) is present
자다 (sleep)	주무시다	(someone respected) sleeps
말하다 (say)	말씀하시다	(someone respected) speaks

드리다 vs 주시다 (give — directionality matters)

Form	Direction	Use
드리다	I give → you (humble, lowering self)	`말씀 드리겠습니다` (I will tell you, humble)
주시다	You give → me (honorific, elevating other)	`알려 주세요` (please tell me)

Mixing them up sounds reversed — 드리다 must elevate the receiver, 주시다 must elevate the giver.

Punctuation — half-width (ASCII)

Korean is unlike Japanese/Chinese — use standard ASCII punctuation, no full-width.

Wrong	Correct
Status: Complete	Status: Complete

Decimal: . Thousands: , Quotation: "..." or '...'

Full-width brackets — title/quotation contexts only

While modern Korean UI uses Western punctuation ("..."), specific contexts DO use full-width brackets:

Bracket	Use for	Example
『』	Book titles	『The Miracles of the Namiya General Store』
「」	Chapter titles, short works, quoted titles within a work	「Chapter 3: The Beginning」
〈〉 or 《》	Movies, albums, songs, exhibitions, performances	〈Parasite〉, 《BE》 (BTS album)

For inline UI prose, prefer Western quotes "..." or '...'. Use full-width brackets only when explicitly citing media titles in editorial / marketing copy.

Spacing (띄어쓰기)

Space between Korean and Latin script/numbers: API 설정 not API설정, 합계 10건 not 합계10건.
No space between a Korean stem and its suffix/particle: 저장하기 not 저장 하기.

Native vs Loanword — prefer native for UI

Avoid (transliterated)	Use (native)
save	saved
set	settings
select	select
cancel	cancel
delete	delete
edit	edit
search	search

Spelling that natives expect (revised orthography):

Wrong	Correct
contents	contents
message	message

Konglish False Friends (콩글리시)

Konglish	Korean meaning	Correct for English
service	free bonus / complimentary	service (only if literally "service")
handphone	hand phone (Konglish)	mobile phone / smartphone
meeting	group blind date	meeting (business meeting)
one shot	"drink in one gulp"	in one go / at once

Calques to avoid

Literal (wrong)	Natural Korean
makes sense	makes sense / is reasonable
at the end of the day	in the end / ultimately
on the table (abstract)	under discussion
the ball is in your court	it's up to you
not really ("not really")	not really / not so
Break a leg	Fighting! / Good luck
Piece of cake	a piece of cake / easy as pie
When pigs fly	when the sun rises in the west

Compound Adjectives

English	Wrong	Correct
X-aware	context aware	context-aware
AI-powered/driven	AI-powered	AI-based / AI-driven

Compound Descriptive Nouns

Decompose English compounds, rebuild naturally.

"mom creators" → 엄마 크리에이터 or 육아 크리에이터 (NOT 어머니 창작자)
"niche creators" → 니치 크리에이터 or 틈새시장 크리에이터
"English-speaking customer service" → 영어 고객 서비스 (compound adjective, not relative clause)

UI Element Reference in Prose

When referencing a UI label by name in prose, use quotes or brackets:

Wrong: 이름의 필드 → Correct: '이름' 필드 or [이름] 필드
Wrong: 계정의 탭 → Correct: '계정' 탭
Generic elements (검색창) need no quotes.

Spatial Metaphor Prepositions

English (figurative)	Use	Don't use
under [category]	from / among	under
on top of (in addition to)	in addition to / besides	on top of
behind the scenes	behind the scenes / backstage	(literal)
within [timeframe]	within / in	inside

Temporal Simile Restructuring

English	Wrong (literal)	Natural
operating like it's 1995	operating like it's 1995	stuck in 1995 / hasn't changed since 1995
stuck in [YEAR]	still operating as it was in [YEAR]	no progress since [YEAR] / still doing things the [YEAR] way

Polysemy — pick the right sense

Word	Wrong (literal)	Correct (contextual)
copy (marketing)	copy	copy / wording
sauce (figurative)	sauce	secret / key element
bug (software)	bug (insect)	bug
resume (verb)	resume	resume

Proper Nouns — use natural Korean forms

Wrong	Correct
Australia	Australia
United States of America	United States
Great Britain	United Kingdom
American English	American English (use X식 for language variants)

Tense / Aspect Fidelity

Don't flatten ongoing/habitual into completed actions.

English (ongoing)	Wrong (past)	Correct (progressive)
we are building	we built	we are building
costs are increasing	costs increased	costs are increasing
announcing X (habitual)	said	goes around saying / tends to say

Question / Confirmation Phrasing

Wrong: 당신은 확실합니까? → Correct: 확실하신가요?
Wrong: 삭제할래? → Correct: 삭제하시겠습니까?
Omit unnecessary subjects.

Brand Name Rules

Brand + Korean noun: space between them. Airbnb 앱 or 에어비앤비 앱.
Technical abbreviations stay as-is: API, URL, ID.

Honorific Suffix 님 / Name Forms

Korean uses the honorific suffix 님 attached to names and titles in formal address. Unlike Japanese -san, Korean does not have a standalone name suffix — instead 님 attaches to titles (job/role), and title + 님 works similarly.

Title + 님 (formal address)

Form	Meaning	Context
Mr. Kim	Mr./Ms. Kim (teacher / respected)	School, formal address
Department Head Lee	Manager Lee	Office, hierarchy
President Park	President/CEO Park	Business
Professor Choi	Professor Choi	Academic
Dr. Jung	Dr. Jung	Medical

UI honorific forms

Form	Meaning	When to use
customer	Dear customer	Customer-facing copy, support, e-commerce
member	Dear member	Membership / subscription apps
guest	Guest	Hospitality, retail, restaurants
user	User	Technical UI — no 님 in dev/admin/dashboards
user	Dear user	Rare; only in very polite consumer copy

Email / greeting addressing

안녕하세요, 김철수 님 — Hello, Mr. Kim Chul-soo (space before 님 after a full name)
김철수 고객님 — Customer Kim Chul-soo
회원님께 — To dear member (with dative particle 께)

Rules

Attach 님 to titles, not bare given names in technical UI.
Use space between full name and 님: 김철수 님, not 김철수님 (though both are seen; space form is more correct in formal copy).
Drop 님 in technical/dev UI: 사용자 ID, 사용자 권한 — never 사용자님 ID.

Greetings & Closing Protocols

Phrase	Meaning	Context
hello	Hello / Hi (universal polite)	Any UI greeting, opening, customer support
goodbye	Goodbye (to person LEAVING)	Said by the person staying
goodbye	Goodbye (to person STAYING)	Said by the person leaving
good morning	Good morning (polite)	Morning greetings, B2B
nice to meet you	Nice to meet you (formal)	First-time greetings
welcome	Welcome (formal)	Onboarding, landing, signup confirmation
welcome	Welcome (warmer, retail/hospitality)	E-commerce, app entrance
thank you	Thank you (formal)	Default polite thanks
thank you	Thank you (slightly warmer)	Friendly polite thanks

Direction rule for 가세요 vs 계세요

The departure direction determines which to use:

The person who is leaving says 안녕히 계세요 (stay well).
The person who is staying says 안녕히 가세요 (go well).

App goodbye screens default to 안녕히 가세요 since the app is "staying" and the user is "leaving".

Empty State Alternatives

Different empty states need different phrasings. Don't use one for all.

English	Korean	When
No results	no results	Search returned 0 hits
No items	no items	List/table empty
No data	no data	Chart/dashboard empty
Nothing to show	nothing to display	Generic placeholder
File not found	file not found	404 / missing resource
No notifications	no notifications	Notification panel
No messages	no messages	Inbox/chat empty
No history	no records	Activity log empty

Avoid 비어 있습니다 (literally "is empty") for search/results — sounds odd. Reserve for explicit container states like 폴더가 비어 있습니다 (the folder is empty).

Calendar / Time Conventions

Item	Consumer apps	B2B / Technical
Time of day	`오전 9시` / `오후 2시 30분`	`09:00` / `14:30` (24h)
Date	`2024년 1월 15일`	`2024-01-15` / `2024.01.15`
Day of week	`금요일` (Friday)	`(금)` (abbreviated)
Relative	`오늘`, `내일`, `어제`, `모레` (today, tomorrow, yesterday, day after)	—

Prefer 오전 / 오후 over AM / PM in consumer-facing copy. Use 24-hour format in admin dashboards, schedule UI, and technical contexts.

Cultural Conventions

Item	Format
Date	`2024년 1월 15일` or `2024.01.15` (NOT `01/15/2024`)
Time	`오후 2시 30분` or `14:30`
Currency	`1,000원` or `₩1,000`

Cost / Estimate Expression Ordering

Pattern A (amount-first): 예상 비용: {credits} 크레딧 ({count}개 언어)
Pattern B (scope + 총): {count}개 언어 총 {credits} 크레딧
Wrong (ambiguous): {count}개 언어 {credits} 크레딧.

Redundant Modifiers — remove

Wrong	Correct
minimum {min} characters	minimum {min} characters / at least {min} characters
save your file	save file (omit possessive)

UI Tone Vocabulary

English	Wrong	Correct
casual tone	casual tone (=fashion)	relaxed tone / informal tone
formal	no formality	formal
professional	(literal)	professional

Self-Check Checklist (run before finalizing)

Accuracy

Particles correct for final 받침 (이/가, 을/를, 은/는, 과/와)
Loanword particles chosen by Korean pronunciation (GPT-5[pa-i-beu]→가, RTL[al-ti-el]→은)
No mechanical artifacts (을(를), 이(가) — pick one)
Speech level consistent throughout (해요체 OR 하십시오체)
UI buttons in stem/noun form; sentences in speech level
Measure words appropriate (개/명/건/가지/번)
Word vs character not confused (단어 vs 글자)
FOR vs PER not confused (~에 대해 vs ~당)
Unit words after numeric placeholders (초/분/시간/일)
Temporal: ~후 for countdowns, ~중 for ongoing, ~이내 for deadlines
Placeholder type markers (형식의, 언어의)
Half-width (ASCII) punctuation
No space before colon
SOV word order
Spacing: gap between Korean ⇄ Latin/numbers; no internal gap (저장하기)
All {variables} and ICU intact
Standard spelling (콘텐츠 not 컨텐츠, 메시지 not 메세지)
Domain terminology uses IT loanwords (아키텍처, 배포, 파이프라인)

Naturalness

UI labels are complete noun phrases (대체 감지 방법)
Cost expressions use amount-first or scope+총 pattern
Tone vocabulary correct (편안한, NOT 캐주얼)
No English calques
Konglish false friends caught (서비스, 미팅, 핸드폰)
Pronouns omitted when context clear (no 당신/너)
Compound adjectives natural (AI 기반, NOT AI 구동형)
Drag-drop verbs correct (놓다 for release, NOT 허용)
Native term over transliteration (저장 > 세이브)
Compound nouns restructured (엄마 크리에이터, NOT 어머니 창작자)
UI labels in prose use quotes/brackets ('이름' 필드)
Spatial metaphors adapted (인기 주제에서, NOT 인기 주제 아래에)
Proper nouns naturalized (호주, 미국, 영국)
Validation messages clear with 및/또는/만
Tense/aspect preserved (~하고 있다 for ongoing)

Worked Example

Source: "Welcome! Please select your file to upload — we support 25+ formats and translate it for 5 languages in {seconds}s. Don't worry, you can cancel at any time."

Wrong (literal): Welcome! Browse your files for upload — we support 25+ formats and translate it in {seconds} per 5 languages. Don't worry, you can cancel anytime.

Issues: 당신의 (redundant), 브라우즈 (Konglish), 서포트 (transliteration), 25+ (not natural), 5언어당 (FOR/PER confusion), {seconds} (missing 초), 캔슬 (use 취소), mixed speech levels (~해요 + ~합니다).

Correct: Welcome! Please select the file to upload. We support 25 or more formats and translate within {seconds} seconds for 5 languages. You can cancel anytime.