How to say "harmless" in Japanese

• 無害むがいCommon
  na-adjective, no-adjectiveThe default choice for 'harmless' in the physical or general sense: something that causes no harm. Fits things like harmless substances or animals in everyday and neutral contexts.
  この島しまではたいていのヘビは無害むがいである。↗

  Most snakes on this island are harmless.
• 当たり障りのないあたりさわりのない
  expression, prenominal modifierCovers 'harmless' only for remarks, topics and similar, meaning inoffensive, safe and bland. Use it when someone avoids saying anything likely to offend, not for physical harmlessness.
  とりあえず、あたりさわりのない話はなしをしておいたよ。↗

  I steered clear of sensitive topics.
• 害のないがいのない
  expression, i-adjectiveDescribes something that does no harm, with an innocuous or benign nuance. A safe alternative to 無害, often suited to describing things as benign or harmless in effect.
• 無毒むどく
  no-adjective, na-adjectiveSpecifically means nonpoisonous or nontoxic. It is the right word for harmless in the sense of containing no poison, not for harmless remarks or trivial matters.
• なんでもない
  expression, i-adjectiveMeans trifling or of no concern, so 'harmless' here suggests something trivial rather than noninjurious. Usually written in kana, and seldom the word you want for genuinely harmless things.
  何なんでもないことに大騒おおさわぎするのはやめなさい。↗

  Stop making a fuss over nothing.

Use 無害 as the general word for harmless; 「害のない」 for benign things; 「当たり障りのない」 for bland remarks; 無毒 for nontoxic; 「なんでもない」 for trivial matters.

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

• 無害むがいharmless
• 当たり障りのないあたりさわりのないharmless (remark, topic, etc.)
• 害のないがいのないharmless
• 無毒むどくnonpoisonous
• なんでもないeasy
• 罪がないつみがないinnocent
• 人畜無害じんちくむがいhaving no influence