LESSON NOTES · レッスンノート

N5Lesson notes · Sep 30, 2026

Cool in Japanese: かっこいい, クール, 涼すずしい and 冷つめたい — four different 'cool's

"Cool" has no single Japanese word — かっこいい for stylish, 涼すずしい for mild weather, 冷つめたい for cold things or people, and いいよ or 大丈夫だいじょうぶ for "I'm cool with that."

English lets one word cover a leather jacket, a spring evening, an unfriendly stare, and "sure, no problem." Japanese splits those four jobs across four different words. The good news: once you sort them by what English cool is doing, the choice is almost automatic.

The basics

What is the Japanese word for "cool" (stylish)?

かっこいい (格好かっこういい). It covers looks, actions, and objects: a person who handles something well, a sleek design, a great performance.

あの人ひと、かっこいいね。 — That person is cool. (casual, about looks or presence) このデザイン、かっこいい! — This design is cool! (casual, about a thing) 今いまの動うごき、かっこよかった。 — That move just now was cool. (casual, past tense)

Notice the last one. かっこいい is built on いい, so it inherits the irregular past tense: いい becomes よかった, not いかった. So it is かっこよかった, never かっこいかった. The same rule applies to negatives (かっこよくない). If that pattern is new, the past tense of adjectives explains the whole system.

Is かっこいい only for men?

No. It is often used for women too, and there it usually means "impressive, admirable" rather than "handsome." Calling a woman かっこいい is a compliment about how she carries herself.

先輩せんぱい、かっこいいです! — Senpai, you're so cool! (polite, admiring)

How do you say "cool" for weather and temperature?

涼すずしい (すずしい) is the pleasant kind of cool: a breeze, an autumn evening, an air-conditioned room. For things that are physically cold to touch, use 冷つめたい (つめたい): a drink, water, or a hand.

今日きょうは涼すずしいですね。 — It's cool today, isn't it? (polite, small talk about weather) この水みず、冷つめたい! — This water is cold! (casual, touching or drinking)

That difference — pleasant versus cold-to-the-touch — is worth learning early. It connects to how Japanese handles temperature more broadly; see hot and warm words like 暑あつい and 熱あつい, and the weather vocabulary list for seasonal small talk.

What about "I'm cool with that"?

That is not about style or temperature at all. It means "that's fine with me," and Japanese says it with いいよ or 大丈夫だいじょうぶ.

それでいいよ。 — I'm cool with that. (casual, agreeing) 私わたしは大丈夫だいじょうぶ。 — I'm cool with it. / I'm fine. (casual, no objection)

大丈夫だいじょうぶ is slippery, though, because it can also mean "no thanks." The full story is in 大丈夫だいじょうぶ: the word that means yes, no, and "are you okay?".

Beyond the basics

What do people actually say instead of かっこいい?

In casual speech かっこいい often shrinks to かっけー. Anime characters and friends use it constantly, and it feels energetic and a bit boyish.

うわ、かっけー! — Whoa, that's cool! (very casual, excited reaction)

イケてる ("looking good, with it") is also used for things and people that are stylish, but it sounds a bit dated to many younger speakers. You will still hear it, but かっこいい is the safer choice.

Is "That's cool!" always かっこいい?

No, and this is the mistake learners make most. In English, "That's cool!" is often just a reaction of interest. In Japanese, saying かっこいい about a story or a fact sounds odd, because かっこいい is about style. The natural reaction is often すごい ("amazing, impressive").

来月らいげつ、京都きょうとに行いくんだ。 — I'm going to Kyoto next month. (casual, sharing news) いいね! — That's cool! (casual, warm reaction) それ、すごいね! — Wow, that's cool! (casual, impressed)

Use いいね for "nice" and すごい for "impressive." Save かっこいい for things that actually look or feel stylish.

What is クール, and how is it different?

クール is the loanword. It most often points at a personality: calm, composed, a bit distant. It can also mean "stylish" (クールなデザイン), but かっこいい is the everyday word for that. In anime it is a character type. A "cool character" (クールキャラ) is the quiet one who rarely shows emotion, and the exact opposite of a loud energetic one.

彼かれはクールな性格せいかくだ。 — He has a cool (calm) personality. (neutral, describing character) クールに見みえるけど、優やさしい。 — She seems cool, but she's kind. (casual, a classic character reveal)

So かっこいい means "looks great," and クール usually means "calm and unbothered." A character can be one, both, or neither.

When does 冷つめたい mean a cold attitude?

冷つめたい also describes people who are unfriendly, in the same way English says "a cold reply." That is the only place where it overlaps with a negative "cool."

彼女かのじょの返事へんじは冷つめたかった。 — Her reply was cold. (casual, past tense of an い-adjective)

Common mistakes

  • Saying かっこいかった. The past of かっこいい is かっこよかった, because いい is irregular.
  • Using かっこいい to react to news. "That's cool" about someone's trip is いいね or すごい, not かっこいい.
  • Using 涼すずしい for a cold drink. 涼すずしい is about air and weather. A cold drink is 冷つめたい.
  • Using クール as your everyday word for "stylish." クールなデザイン is fine, but for a person クール usually means calm and composed, and can sound aloof. かっこいい is the default praise.
  • Treating 大丈夫だいじょうぶ as always "yes." Depending on tone, it can mean "no thanks."

Which "cool" is which?

English "cool" Japanese Feel
stylish, impressive かっこいい The standard word, for people, things, actions
stylish, very casual かっけー Slangy, energetic
stylish (slightly dated) イケてる Still understood, older-sounding
"That's cool!" (reaction) いいね / すごい Nice / impressive, depending on the news
calm personality クール Anime character type: quiet, composed
pleasant air, mild weather 涼すずしい Breeze, autumn evening
cold to the touch 冷つめたい Drink, water, hand
cold attitude 冷つめたい Unfriendly person or reply
"I'm cool with that" いいよ / 大丈夫だいじょうぶ Fine with me

FAQ

Is かっこいい written with kanji? Yes, 格好かっこういい, but it is almost always written in hiragana or katakana (かっこいい, カッコいい). Both forms are normal.

Is かっこかわいい a real word? Yes, かっこかわいい is used for something both stylish and cute. It is more of a modern, casual coinage than a dictionary word.

How do I say "cool" as praise in polite speech? かっこいいですね works in polite speech. For a boss or a customer, 素敵すてきですね ("that's lovely") is often safer.

Can I say クール to mean "cool" in English style? Yes. クールなデザイン and クールな色いろ are normal. For a person, though, クール mostly means calm and composed, and かっこいい is the more common everyday praise.

Is 涼すずしい the same as 寒さむい? No. 涼すずしい is pleasantly cool, 寒さむい is cold weather that makes you want a jacket. 涼すずしい never sounds unpleasant.

Practice

Build each answer before opening it. Questions 3 and 4 are a pair — same English "cool", different Japanese.

1. Say "That performance was cool" in the past tense, casually.

Show answer

今いまのパフォーマンス、かっこよかった — かっこいい is built on いい, so the past is かっこよかった (not かっこいかった).

2. A friend says they got a new job. How do you react with "That's cool!" naturally?

Show answer

すごいね! or いいね! — it is news, not style, so かっこいい would sound odd.

3. It is a pleasant autumn evening. How do you say "It's cool today"?

Show answer

今日きょうは涼すずしいですね — 涼すずしい describes pleasant, mild air.

4. You touch a glass of iced water. How do you say "It's cool / cold"?

Show answer

冷つめたい — this is the pair to question 3. 冷つめたい is for things that are cold to the touch, not for the weather.

5. In an anime, a character is quiet and hides their emotions. Which word describes them?

Show answer

クール — it describes a calm personality, the "cool character" type.

6. Someone asks "Is this plan okay?" and you agree. How do you say "I'm cool with that"?

Show answer

それでいいよ or 大丈夫だいじょうぶ — this cool means "fine with me," not style or temperature.

7. What is the very casual, shortened form of かっこいい?

Show answer

かっけー — used in excited, casual speech.

8. What is wrong with 涼すずしい水みず?

Show answer

It should be 冷つめたい水みず. 涼すずしい is for air and weather, not for a drink you touch.

9. How do you say "Her reply was cold" in the past tense?

Show answer

彼女かのじょの返事へんじは冷つめたかった — 冷つめたい can describe an unfriendly attitude, and the past of an い-adjective changes い to かった.

In a trial lesson, describe a person, a drink and a breeze, and see that かっこいい, 冷つめたい and 涼すずしい are not interchangeable.

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.

かっこいい	かっこいい — cool, stylish
かっけー	かっけー — cool (very casual)
イケてる	イケてる — stylish, looking good
すごい	すごい — amazing, impressive
いいね	いいね — nice, sounds good
クール	クール — calm, composed
涼しい	すずしい — pleasantly cool
冷たい	つめたい — cold (to the touch), cold (attitude)
大丈夫	だいじょうぶ — fine, okay
性格	せいかく — personality
返事	へんじ — reply

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, since "cool" is one of the first English words learners try to translate. 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

More “Describing Things: Japanese Adjectives & Opposites” articles →

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