AI in Korean: Honorifics, Spacing and Replies

AI in Korean works well for everyday writing, but it fails in predictable places: the wrong speech level, odd spacing, unnatural word order and numbers read the wrong way. Korean marks respect inside the grammar of every sentence, so a reply that is correct in meaning can still sound rude, cold or childish to the person who reads it. If you write to customers, colleagues or partners in Korea, you need to tell the assistant who is speaking, who is listening and how formal the message should be.

This guide shows how to prompt for natural Korean, how the speech levels differ, which details to check before sending and how to review business replies without speaking the language fluently. The examples work with any capable assistant, including Mio.

Why AI in Korean needs more instructions than English

In English a sentence is polite or casual mostly because of the words around it. In Korean the verb ending itself carries the relationship between speaker and listener. A model that has seen far more English than Korean tends to pick a default ending, and that default may not suit your situation. The result is text that is grammatical and still socially wrong.

There are three more reasons to be careful. First, Korean is written in Hangul, a phonetic alphabet, but spacing rules between words are subtle and models often get them slightly wrong. Second, Korean drops subjects and objects whenever the context makes them clear, so a literal translation from English can feel stuffed with unnecessary pronouns. Third, many business terms exist as both native Korean words and loanwords from Chinese or English, and the register differs between them.

None of this makes AI in Korean unusable. It means you should give the assistant the same context you would give a human translator: audience, relationship, purpose and channel. The more of that you provide, the fewer corrections you will make afterwards. Our general guide to prompting in languages other than English covers the basics, and this article adds what is specific to Korean.

Speech levels and honorifics

Korean has several speech levels. For most business and customer writing you need only two of them, plus an awareness of the others so that you can spot a mistake. The overview of Korean speech levels gives the full system. The table below is a practical summary.

Level	Typical use	Sounds like	Use in business writing
Formal polite (hapsyo-che)	Announcements, official letters, presentations, first contact	Respectful and distant	Yes, for formal documents and notices
Informal polite (haeyo-che)	Everyday customer chat, friendly e-mails, social media	Respectful and warm	Yes, for most customer replies
Plain or intimate (banmal)	Close friends, family, younger people you know well	Casual, can be rude if misused	No, never for customers
Old or literary forms	Historical text, some religious or ceremonial writing	Archaic	No

Honorifics also appear in vocabulary and particles. Titles such as a surname plus a job title, an honorific suffix after names and special verbs for actions performed by a respected person all change the text. The assistant will usually handle common cases, but ask it explicitly: “Use formal polite endings, address the reader by surname and title, and use honorific verb forms for the customer’s actions and humble forms for ours.”

Name order matters as well. Korean names put the family name first, and many people dislike being addressed by a given name alone. If you are writing to a person you have not met, include the full name and title in the prompt and tell the assistant not to shorten it.

A prompt pattern for natural Korean

Start every Korean task with a short brief. A reliable pattern has six parts: who writes, who reads, purpose, speech level, length and facts that must not change. Here is an example for a customer reply.

Write a reply in Korean.
Writer: support agent at an online shop.
Reader: a customer who asked where her parcel is; I know only her surname, Kim.
Level: informal polite (haeyo-che), warm but professional.
Facts that must not change: order number 48213, shipped on 3 March,
carrier tracking link below, delivery in 2-3 working days.
Length: under 90 words. No emoji. Do not promise a delivery date.
After the reply, list any phrase that may sound too casual or too stiff.

The final line is the most useful part. When you ask the assistant to flag its own risky phrases, you get a list you can check with a native speaker or a trusted dictionary instead of re-reading the entire text. For longer pieces such as a newsletter, ask for two versions, one formal and one friendly, and compare them side by side.

Keep a small style sheet and paste it at the start of each session or store it in a project. It should hold your company name in Korean and in Latin letters, your preferred spelling for product names, forbidden words, greeting and closing lines and whether you address customers as “customer” or by name. Mio can keep such instructions in a project so that every reply follows them. See our guide to projects and memory for the setup.

Spacing, particles and word order

Korean spacing rules decide where a space goes between words and which small words attach to the previous one. Particles that mark subject, topic and object attach directly to nouns. Models usually get these right, but errors appear in long compound nouns, in numbers followed by counters and in text that was pasted from English with its original punctuation.

Check these points in every draft:

Counters. Korean uses different counting words for people, objects, animals and events, and numbers before them come in two systems.
Particles. Look for a repeated topic particle in one sentence or a missing object particle in a short instruction.
Long compound nouns. Brand and product names should be written exactly as you give them, not re-spaced.
Punctuation. Use the punctuation style your readers expect: straight quotation marks in digital text are common, and a full stop at the end of a polite sentence is standard.
Foreign words. Decide whether a technical term stays in Latin letters, is written in Hangul or appears with a short explanation.

Word order is subject, object, verb, with modifiers before the thing they modify. A good draft therefore puts the main verb at the end of the sentence, and a very long sentence is often a sign of a literal translation. Ask the assistant to split long sentences and to keep each one to a single idea.

Numbers, dates and money

Korean has two number systems: native Korean numerals and Sino-Korean numerals. Dates, prices, phone numbers and minutes use the Sino-Korean system, while hours, ages and many counters use the native one. Models make mistakes here more often than in plain prose, so verify every figure.

Write dates in year, month, day order. Name the currency clearly, and if the amount is in euros or dollars and the reader expects won, say so and give the conversion source. Do not let an assistant convert currencies from memory. Rates change daily, so use a rate you have checked and write the date of the rate next to it. A short instruction such as “Copy every number and date from my source exactly; do not convert or round” prevents most problems.

Phone numbers and addresses deserve the same care. Korean addresses start with the largest unit and end with the smallest, which is the opposite of many Western formats. If the text will go on a parcel label or into a form, give the address in the format the receiving system expects and ask the assistant only to check it, not to rewrite it.

Business replies, e-mails and customer support

Business Korean follows conventions that differ from English-language e-mail. Messages usually open with a greeting and an introduction of the writer’s name and company, include a short sentence of thanks or apology and end with a polite closing. Directness is valued less than courtesy, so a blunt translation of an English “No” can sound abrupt.

For refusals and bad news, ask for a softer structure: thanks, explanation, alternative, apology. For requests, ask the assistant to state the request once, politely and clearly, and to avoid stacking several favours in one message. For reminders about payment, ask for a firm but respectful tone and have a native speaker review the first template you use.

Support teams can combine the assistant with a library of approved answers. Paste your approved answer in your own language, ask for a Korean version at the right level and keep the result in a shared document after it has been checked. Next time, reuse the approved version and adapt only the facts. Our guide to AI for customer support explains how to organise such a library.

Translation quality and how to check it

You do not need to read Korean to run a useful quality check. Use these steps for any important text.

Back-translation. Ask the assistant, in a new chat, to translate the Korean text back into your language without seeing the original. Compare meaning, not wording.
Fact table. Ask for a table of every name, number, date and promise in the Korean text beside the same items in your source. Differences are easy to spot.
Register check. Ask which speech level each sentence uses and whether any sentence mixes levels. Mixed levels in one message are a common sign of an error.
Native review. For legal text, contracts, medical information and anything public, have a native speaker review the final version.

Our guide to checking AI translation quality goes deeper, and the article on AI for translators shows how professionals build review into their workflow. Machine output is a strong first draft, not a certified translation.

Where AI in Korean is strong and where to be careful

Assistants are strong at summarising Korean articles, drafting routine replies, explaining grammar, rewording text at another level of formality and turning notes into clean paragraphs. They are weaker at slang, regional speech, wordplay, very recent expressions and text that depends on cultural references.

Be careful with names of people and places. Romanisation of Korean names follows several systems, and a person’s own spelling may not follow any of them. Always use the spelling the person uses. Be careful with legal and financial terms, which have precise meanings and are easy to translate loosely. And be careful with humour and marketing slogans: a clever line in English rarely survives a literal translation.

When the stakes are higher, ask for alternatives. A prompt such as “Give three versions of this headline in Korean, one literal, one natural and one punchy, and explain the difference” turns the assistant into a brainstorming partner while the final choice stays with a person who can judge the result.

Working with Mio in Korean

Mio understands and writes Korean, so you can ask in your own language and request the answer in Korean, or write in Korean directly. The assistant routes each request to a suitable model for you, so you never choose one yourself. For Korean documents, upload a PDF or Word file on a paid plan and ask for a summary, a list of action items or a translation of selected parts. Research mode searches the web and shows its sources, which helps when you need to verify a term or a company name.

The free plan covers Chat and Write, which is enough for most short replies. File uploads, Research and memory arrive with the paid plans, and you can compare them on the pricing page. Chats and files are not used to train models, and you can export or delete them at any time. Still, follow the same rule as with any tool: do not paste personal data, contracts or confidential details unless you need to, and replace names with placeholders where you can.

A simple checklist before you send

Did you state the speech level and the relationship between writer and reader?
Do names, titles and company names appear exactly as the person or company writes them?
Are all numbers, dates, prices and addresses copied from the source and not converted from memory?
Does the message use one speech level from start to finish?
Did you run a back-translation or fact table for anything that matters?
Has a native speaker seen the first version of every template you will reuse?

Frequently Asked Questions

Can AI write Korean that sounds natural?

Often yes, especially for e-mails, summaries and routine replies, as long as you state the speech level and context. It can still choose a slightly wrong tone or an unnatural phrase. For public text, contracts or marketing, have a native speaker read it before you publish or send anything important.

Which speech level should I use for customers?

Most customer replies use the informal polite level, which is respectful and warm. Formal notices, official letters and first contact with a senior person call for the formal polite level. Never use plain casual speech with customers. Tell the assistant the level explicitly instead of letting it choose a default.

Do I need to speak Korean to check the result?

Not for a basic check. Ask for a back-translation in a fresh chat, a table of numbers, names and dates and a list of phrases that might sound too casual or too stiff. These steps catch most errors. Important documents should still be reviewed by a native speaker or a professional translator.

Is AI translation of Korean as good as for European languages?

Quality has improved a great deal, but results vary by topic and text type. Everyday and business text is usually good, while slang, dialect, poetry and cultural references remain harder. Test the assistant on a sample of your real material and have it reviewed before you rely on it for volume.

Can Mio handle Korean documents?

Yes. On a paid plan you can upload PDF, Word, text or image files and ask for summaries, translations of selected sections or lists of key points. Check the live pricing page for file size limits, and review the output before sharing it, particularly names, numbers and dates.

Should I paste customer names into the prompt?

Only when you must. Use placeholders for names, addresses and order details, then insert the real data into the final text yourself. This reduces the risk of leaking personal data and makes your prompts reusable. If you do need real names, make sure the spelling is exactly the one the person uses.

The Bottom Line

AI in Korean is a fast and capable drafting partner when you give it the speech level, the relationship and the facts, and when you check names, numbers and tone before sending. Use back-translation and a fact table for anything that matters, and keep a native speaker in the loop for public or legal text. You can start for free and compare plans on the Ask Mio pricing page.

AI in Korean: Honorifics, Spacing and Business Replies