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N5Lesson notes · Oct 4, 2026

Clean in Japanese: きれい (kirei), 掃除そうじ (souji), and the な-adjective trap

"Clean" in Japanese is きれい (kirei) when you mean a clean, neat room, and 掃除そうじする (souji suru) when you mean "to clean" it — and きれい ends in い but behaves as a な-adjective, so it is きれいな部屋へや and きれいじゃない, never きれくない.

Search for "clean in Japanese" and you will find two different English words hiding under one query. One is the adjective ("a clean room"). The other is the verb ("to clean the room"). Japanese keeps them apart, and it adds a few more words for hygiene, tidying up, and washing.

The adjective きれい also means "pretty" and "beautiful", which is a bonus and a source of confusion at the same time. This post sorts it out in the order you will meet it: describing something clean, doing the cleaning, and then the small words that fill the gaps.

The basics

How do you say "clean" in Japanese?

The word is きれい (綺麗きれい). It describes a place or thing that is free of dirt and in good order, and it is almost always written in hiragana.

この部屋へやはきれいです。 — This room is clean. (polite, neutral, the safe default) きれいなトイレですね。 — It's a clean toilet, isn't it. (polite, a small compliment in a shop or station)

Same word, different object: きれいな花はな is "a pretty flower" and きれいな人ひと is "a beautiful person". Japanese does not force you to choose between "clean" and "pretty". Context does it for you, and when the object is a room, a desk, or a kitchen, it means clean and tidy.

For the "beautiful" side of the word and its neighbors, see Japanese words for beautiful.

Why is きれい the classic trap?

Because it ends in い but is not an い-adjective. It is a な-adjective, so it needs な before a noun and じゃない for the negative, exactly like 静しずか (quiet) or 便利べんり (convenient).

きれいな部屋へや — a clean room (な before the noun) この部屋へやはきれいじゃないです。 — This room isn't clean. (polite negative) 昨日きのうの駅えきはきれいでした。 — The station was clean yesterday. (polite past)

An い-adjective would be きれいい, きれくない, きれかった. None of those exist. The ending い in きれい is simply part of the word, the way the い in 嫌きらい (disliked) is. If the い-versus-な split is still blurry, い-adjectives vs な-adjectives explains how to tell them apart, and convenient in Japanese shows the same な pattern with another very common word.

How do you say "to clean" in Japanese?

Use 掃除そうじする (そうじする). It means cleaning a space: sweeping, vacuuming, wiping, the whole job. The thing you clean takes を.

毎週まいしゅう、部屋へやを掃除そうじします。 — I clean my room every week. (polite, habit) トイレを掃除そうじしてください。 — Please clean the toilet. (polite request) 掃除そうじ、終おわった? — Is the cleaning done? (casual, family or friends)

Think of it as cleaning a place. For washing things with water, the verbs below fit better.

What does きれいにする mean, and when do you use it?

きれいにする means "to make something clean". It works for almost anything, and it is a handy fallback when you do not know the exact cleaning verb.

テーブルをきれいにしてください。 — Please clean the table. (polite request) 使つかったあとは、きれいにしましょう。 — Let's clean up after we use it. (polite, a common rule at shared spaces)

Notice that きれい becomes きれいに here. When the adjective modifies a verb, な-adjectives take に. The same word turns up in 手てをきれいに洗あらう, "wash your hands properly".

Beyond the basics

What's the difference between きれい and 清潔せいけつ?

清潔せいけつ (せいけつ) means hygienic or sanitary, and きれい means clean-looking and neat. Both are な-adjectives. きれい is about how something looks. 清潔せいけつ is about whether it is actually free of germs and dirt, and it sounds more formal and a little clinical.

このホテルは清潔せいけつです。 — This hotel is clean/hygienic. (polite, a review-style sentence) 清潔せいけつな手てで食べ物たべものを触さわってください。 — Please touch the food with clean hands. (polite, a hygiene instruction) 彼かれは清潔感せいけつかんがある。 — He gives a neat, well-groomed impression. (neutral, about a person's grooming)

清潔感せいけつかん is worth knowing. It describes the fresh, tidy impression of a person: clean clothes, neat hair. It is a compliment in everyday Japanese and does not mean the person is a germ-free object.

What's the difference between 掃除そうじする, 片付かたづける, and 洗あらう?

They cover different jobs, and Japanese uses a different verb for each.

部屋へやを片付かたづけなさい! — Tidy up your room! (a parent's command, anime classic) 机つくえの上あが片付かたづいている。 — The desk is tidy. (neutral, describing the state) 手てを洗あらってから食たべます。 — I wash my hands before I eat. (polite) お皿さらを洗あらいます。 — I wash the dishes. (polite)

片付かたづける (かたづける) means putting things away and tidying up, not scrubbing. 洗あらう (あらう) means washing with water or soap: hands, dishes, clothes, the car. 掃除そうじする is the whole room-level cleaning. You can 片付かたづける a room and then 掃除そうじする it. Notice 片付かたづける takes an object (を) and 片付かたづく describes the state by itself, which is why the desk example uses 片付かたづいている.

Where do 大掃除おおそうじ and お掃除そうじロボット fit in?

大掃除おおそうじ (おおそうじ) means a big, thorough cleaning. In Japan it is also a custom: people do an extra-thorough clean of the home near the end of the year, so the new year can start fresh. お掃除そうじロボット is a robot vacuum, and the お in front is the polite or friendly marker that product names often carry.

年末ねんまつに大掃除おおそうじをします。 — We do a big cleaning at the end of the year. (polite, the custom) お掃除そうじロボットが部屋へやをきれいにしてくれる。 — The robot vacuum cleans the room for me. (neutral, a favor done for you)

In school anime you will also hear 掃除当番そうじとうばん (cleaning duty): the students take turns cleaning their own classroom. It is a real scene in many Japanese schools and shows up in anime constantly, usually with someone slacking off.

How do you talk about someone who loves cleanliness?

Add 好すき to きれい. きれい好すき (きれいずき) describes a person who likes things neat and clean.

彼かれはきれい好すきだから、部屋へやがいつもきれいだ。 — He loves cleanliness, so his room is always clean. (neutral) 私わたしはあまりきれい好すきじゃない。 — I'm not really a neat freak. (casual, self-deprecating)

How do you say "dirty"?

The usual word is 汚きたない (きたない), an い-adjective, so 汚きたない部屋へや is "a dirty room". It is blunt. A softer way to say a place is not clean is to negate きれい: きれいじゃない, which sounds less harsh than 汚きたない. This post only covers the short version; 汚きたない deserves its own write-up. The longer guide, dirty in Japanese, separates 服ふくが汚よごれた (my clothes got dirty) from 服ふくを汚よごした (I dirtied them) and shows why anime heroes shout 汚きたないぞ at cheaters.

Can you use きれい to compliment someone?

Yes, but it means "beautiful", and it can sound too direct depending on who you say it to.

きれいな字じですね。 — What beautiful handwriting. (polite, a safe compliment) きれいに食たべましたね。 — You ate every bit neatly. (polite, said about an empty plate)

That second line is a lovely extra meaning. きれいに食たべる means eating everything on the plate with no mess left, and it is praise, especially at a meal.

Common mistakes

  • Treating きれい like an い-adjective. きれくないです and きれかったです are wrong. Use きれいじゃないです and きれいでした.
  • Skipping な. きれい部屋へや is incomplete. It is きれいな部屋へや.
  • Using 掃除そうじする for "wash". 手てを掃除そうじする sounds like you are cleaning your hands like a room. Use 手てを洗あらう.
  • Using きれい for hygiene when 清潔せいけつ fits better. A restaurant can look きれい but a health inspection checks 清潔せいけつ. For hygiene talk, 清潔せいけつ is the sharper choice.
  • Telling someone their room is 汚きたない. Technically fine, but very blunt. きれいじゃないね is the softer choice among friends.

Which word do I use?

Word Reading Type Meaning Example
きれい kirei な-adjective clean, neat, pretty きれいな部屋へや
清潔せいけつ せいけつ な-adjective hygienic, sanitary 清潔せいけつなキッチン
汚きたない きたない い-adjective dirty 汚きたない靴くつ
掃除そうじする そうじする verb to clean a room or place 部屋へやを掃除そうじする
片付かたづける かたづける verb to tidy up, put away おもちゃを片付かたづける
洗あらう あらう verb to wash 手てを洗あらう
きれいにする きれいにする verb phrase to make clean 机つくえをきれいにする
大掃除おおそうじ おおそうじ noun big cleaning (often year-end) 年末ねんまつの大掃除おおそうじ

FAQ

Is きれい an い-adjective? No. It looks like one because it ends in い, but it is a な-adjective: きれいな部屋へや, きれいじゃない, きれいでした.

Does きれい mean clean or pretty? Both. For a room, a desk, or a table it means clean and neat. For a person, a flower, or a view it means pretty or beautiful. The object tells you which one it is.

What's the difference between 掃除そうじ and 片付かたづけ? 掃除そうじ is cleaning a place with a broom, a vacuum or a cloth. 片付かたづけ is putting things back where they belong. In real life you tidy first and then clean.

How do you say "wash your hands" in Japanese? 手てを洗あらってください. For clothes and dishes you use 洗あらう as well. 掃除そうじする is for rooms and places, not things you wash with water.

Is 清潔せいけつ the same as きれい? Close, but not the same. きれい is how something looks. 清潔せいけつ is whether it is hygienic. You can use either for a hotel room, but 清潔せいけつ sounds more formal.

How do you say "I cleaned my room"? 部屋へやを掃除そうじしました. If you mainly put things away, you can say 部屋へやを片付かたづけました.

Practice

Build each answer before opening it. Questions 1 and 2 are a pair — the same word as a な-adjective in two forms.

1. Say "This room is clean" in polite Japanese.

Show answer

この部屋へやはきれいです — きれい is a な-adjective, so です follows it directly.

2. Say "This room isn't clean."

Show answer

この部屋へやはきれいじゃないです — な-adjectives use じゃない. きれくないです is wrong.

3. What goes before the noun in "a clean room"?

Show answer

きれいな部屋へや — な-adjectives need な before a noun.

4. Which verb means "to clean the room": 洗あらう or 掃除そうじする?

Show answer

掃除そうじする — 部屋へやを掃除そうじする. 洗あらう is for washing things with water, like hands or dishes.

5. Say "Please wash your hands."

Show answer

手てを洗あらってください — 洗あらう is the verb for washing with water.

6. A parent says 部屋へやを____なさい to make a child put things away. Which verb fits: 掃除そうじし or 片付かたづけ?

Show answer

片付かたづけ — 片付かたづけなさい means "tidy up". It is about putting things away, not scrubbing the floor.

7. Which word fits a hygiene sign: きれい or 清潔せいけつ?

Show answer

清潔せいけつ — 清潔せいけつ is about being hygienic, and it is the more formal choice for hotels, kitchens and hands.

8. How do you say "to make the table clean"?

Show answer

テーブルをきれいにする — きれい becomes きれいに when it modifies a verb.

9. What is the year-end custom of thoroughly cleaning the home called?

Show answer

大掃除おおそうじ — a big, thorough cleaning, often done near the end of the year.

きれい is a な-adjective, so in a trial lesson, describe a clean room, a tidy desk and a pretty view, and check the な each time.

Vocabulary from this article

Tap the block to select all of it, then copy. In Anki: File → Import, note type Basic, separator Tab — the first column becomes the front, the second the back.

きれい	きれい — clean, neat, pretty (な-adjective)
清潔	せいけつ — hygienic, sanitary (な-adjective)
掃除する	そうじする — to clean (a room)
片付ける	かたづける — to tidy up, put away
洗う	あらう — to wash
きれいにする	きれいにする — to make clean
大掃除	おおそうじ — big cleaning (often year-end)
お掃除ロボット	おそうじロボット — robot vacuum
掃除当番	そうじとうばん — cleaning duty
きれい好き	きれいずき — someone who loves cleanliness
汚い	きたない — dirty
部屋	へや — room

I'm Yuuki, a Japanese teacher based in Tokyo. I've taught on italki as a Top 1% teacher and watched over 1,500 anime, so most of the example sentences on this blog come from lines I've actually heard students ask about — including this one, which comes up in nearly every beginner's first few lessons. For practice with feedback, Book a trial lesson · $13, or work through Japanese practice exercises first.

Sources: the author's own lessons and standard reference grammars.

More drills like the ones above, plus a timed JLPT-style mock test: Practice · N5 · Read something at this level: JLPT N5 stories with audio

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