日本語道場

Nihongo Dojo — N3 → N2

Grammar

N3

～かいがある

~kai ga aru

it's worth it

When to use it

Use ～かいがある／かいがあった when you want to state that effort, waiting, or hardship paid off — that the result justified the trouble. In business writing it typically appears in the past (～した甲斐があって／甲斐がありました) when reporting a favorable outcome, or in the negative (甲斐がない) to signal wasted effort. The ます-stem form (やりがい・働きがい) has become a noun in its own right and is common in HR and recruiting language.

Formation

  • Verb (た-form) + 甲斐（かい）がある／あった／あって：交渉した甲斐があった
  • Verb (ます-stem) + がいがある（甲斐 voices to gai）：やりがい・働きがい・待ちがい少ない
  • Noun + の + 甲斐がある／あって：努力の甲斐があって（の is often dropped in stiff written style: 努力の甲斐あって）
  • i-adjectives / na-adjectives: do not attach; recast with a verb (例：安くできた甲斐があった)
  • Negative: 甲斐がない／甲斐もなく — 「説明した甲斐がない」
  • Often written 甲斐 in documents, かい／がい in casual text.

Examples

  • Our repeated rounds of negotiation paid off — we landed the contract.

  • Staying up all night to redo the materials was worth it.

  • Thanks to everyone's efforts, sales are up 20% year on year.

  • It seems laying the groundwork in advance was for nothing.

  • I want junior staff to hear that this is a rewarding place to work.