How to say "quick" in Japanese

• 早いはやいJLPT N5approx.Common
  i-adjectiveThe broadest adjective for speed: something that happens, moves, or is done fast — a quick reply, a quick decision. For the ordinary sense of 'quick', this is the safe choice.
  子供こどもは成長せいちょうが早はやい。↗

  Children grow very quickly.
• 素早いすばやいJLPT N1approx.Common
  i-adjectiveCovers 'quick' for physical movement and reactions: nimble, agile, swift. Think of an athlete's or animal's rapid, agile motions — it stresses agility and quick reflexes more than mere speed of occurrence.
  そのクモは素早すばやい反撃はんげきをする。↗

  The spider responds with a swift attack.
• クイックCommon
  prenominal modifierThe English loanword. It appears chiefly in set phrases, service names, and advertising; for ordinary description of something quick, it is seldom the word you want.
• 速やかすみやかCommon
  na-adjectiveA formal word for 'prompt' or 'speedy', typical of written notices and business language: it concerns promptness of action or response rather than the physical speed of a moving thing.
  決定けっていの後あとすみやかに実行じっこうに移うつして欲ほしい。↗

  I want quick action subsequent to the decision.
• 早急そうきゅうJLPT N1approx.Common
  na-adjective, no-adjectiveBusiness and official language for 'immediate, prompt': used when urging that a matter be dealt with without delay, as in emails or documents pressing for a quick response.
  １月がつ２０日にち（月曜日げつようび）の午前中ごぜんちゅうに最終さいしゅうの議事ぎじ事項じこうを出だしますので、早急さっきゅうにお返事へんじを下ください。↗

  We'll release the final agenda on the morning of Monday, January 20, so please reply quickly.

Choose 「早い」 for general speed, 「素早い」 for nimble movement or reactions, 「クイック」 in loanword set phrases and service names, 「速やか」 for formal, written 'prompt', and 早急 for urgent business promptness.

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

• 早いはやいfast
• 素早いすばやいquick
• クイックquick
• 速やかすみやかquick
• 早急そうきゅうimmediate
• 手早いてばやいnimble
• 機敏きびんquick
• 手っ取り早いてっとりばやいquick
• 足早あしばやfast (walking)
• 敏捷びんしょうnimble
• 敏びんquick
• すばしっこいquick
• しゃしゃquick
• はかばかしいquick
• 速急そっきゅうimmediate
• 簡易的かんいてきsimple
• トントン拍子とんとんびょうしeasy
• 気が早いきがはやいhasty
• 気の早いきのはやいhasty
• 迅速じんそく(very) quick
• 簡単かんたんbrief
• 早はやquick
• 慌ただしいあわただしいrapid
• 安易あんいeasygoing
• 尻軽しりがるquick
• 草々そうそうsimple
• はしっこいagile