How to say "tough" in Japanese

• きついJLPT N3approx.Common
  i-adjectiveCovers tough as demanding or severe — a tough schedule, tough work, tough conditions. The nuance is strain: something that demands a lot and is hard to keep up with.
  フーッ、この坂道さかみちはきついよ。でも帰かえりは楽らくだよね。↗

  Whew! This is a tough hill. But coming back sure will be a breeze.
• 硬いかたいJLPT N4approx.Common
  i-adjectiveMatches tough only in the physical sense: hard, solid things, or food that is tough to chew. For tough meaning difficult or demanding, this is not the word you want.
  卵たまごは硬かたくゆでてください。↗

  Boil the eggs hard.
• 苦しいくるしいJLPT N3approx.Common
  i-adjectiveTough in the sense of hard to endure: painful, difficult circumstances, tough times, hardship. The nuance is inner suffering — you feel the difficulty, as in financial hardship or a desperate struggle.
  苦くるしい、やめろ。↗

  It's so painful. Stop it!
• ハードCommon
  na-adjective, no-adjectiveA loanword from English, covering tough as in intense or demanding: hard training, a tough schedule, a heavy workload. The nuance is intensity and how much something takes out of you.
  ウーッ、今日きょうの練習れんしゅうはいつになくハードで辛つらい。↗

  Whoo! Today's practice is tough - much harder than usual.
• タフCommon
  na-adjectiveTough in the sense of resilient and hard to wear down: a tough person who keeps going under pressure, physically or mentally. The nuance is durability and stamina rather than difficulty.
  彼かれはタフだから少すこしのことではへこたれない。↗

  He won't be easily discouraged, because he's a tough guy.

Choose 「きつい」 for demanding, severe conditions, 「硬い」 for physically hard things, 「苦しい」 for painful, hard-to-endure situations, 「ハード」 for intense, demanding loads, and 「タフ」 for a person's resilient toughness.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

• きついtough
• 硬いかたいhard
• 苦しいくるしいpainful
• ハードhard
• タフtough
• 強靭きょうじんtough
• シビアsevere
• 手ごわいてごわいdifficult
• 強いつよいstrong
• ハードボイルドhard-boiled (person, style, etc.)
• 厳格げんかくstrict
• 強硬きょうこうfirm
• 不敵ふてきdaring
• 気丈きじょうstout-hearted
• こわいtough
• しぶといtenacious
• したたかtough
• 世知辛いせちがらいtough (world)
• 精悍せいかんvirile
• 骨っぽいほねっぽいbony
• 取りにくいとりにくいdifficult (to obtain, receive permission, access, etc.)
• 荒くれ男あらくれおとこrowdy fellow
• 線が太いせんがふといimpressive
• やりにくいhard-to-do
• やりづらいhard-to-do
• 堅強けんきょうrobust
• 野性的やせいてきwild
• つらいtough
• 頑強がんきょうtough
• だにhoodlum
• つらたんtough
• 気丈夫きじょうぶstout-hearted
• スパルタstrict
• えらいtiring
• 辛いからいpainful