How to say "breadth" in Japanese

• 幅はばJLPT N3approx.Common
  nounThe default word for breadth or width of a physical object, such as a road, ribbon, or room. It is also used figuratively, as in the breadth of a difference or of someone's interests.
• 横幅よこはばCommon
  nounExplicitly names the horizontal dimension: the breadth or width of something measured side to side, as opposed to its length or height. Useful when you must distinguish the horizontal measurement clearly.
  その長ながさと横幅よこはばを１０で割わりなさい。↗

  Divide its length and breadth by ten.
• 横よこJLPT N5approx.Common
  nounRefers to the side-to-side orientation or direction itself rather than a measurement. It can be glossed as width or breadth, but it really means the horizontal aspect, not the act of measuring breadth.
  道みちが濡ぬれていたので、車くるまは横よこにスリップしたにちがいない。↗

  As the road was wet, the car must have slipped sideways.
• 間口まぐちCommon
  nounCovers figurative breadth only: the scope or range of one's knowledge or work. For literal physical breadth it is not the word you want; its core sense is the frontage or opening width of a building.
• 広さひろさJLPT N2approx.Common
  nounExpresses the broadness or overall size of an area — how spacious something is. It can be rendered as width or breadth, but it emphasizes expanse rather than a specific measured dimension.

For physical breadth use 幅 or the more explicit 横幅, with 「広さ」 emphasizing overall expanse; 横 refers to the horizontal dimension itself; 間口 covers figurative breadth of knowledge or work.

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

• 幅はばwidth
• 横幅よこはばbreadth
• 横よこside-to-side (as opposed to front-to-back)
• 間口まぐちbreadth (e.g. of one's knowledge)
• 広さひろさwidth