が早いか

“No sooner had … than … / The moment …” → Used to express that Action B happens immediately after Action A, emphasizing speed and suddenness, often with a sense of automatic reaction.

N1

Meaning

“No sooner had … than … / The moment …” → Used to express that Action B happens immediately after Action A, emphasizing speed and suddenness, often with a sense of automatic reaction.

Formation

Verb (dictionary form) + が早いか

Explanation

が早いか is used when the speaker wants to show that:

  • Action A occurs

  • Immediately, Action B follows

  • There is virtually no time gap

The focus is on how fast the second action happens after the first.
It often implies that the reaction is instinctive or inevitable, not carefully planned.

This grammar appears mainly in:

  • written narratives

  • descriptive reports

  • novels

  • JLPT N1 reading passages

It sounds unnatural in everyday conversation.

💡 Core nuance:
“The instant X happened, Y followed almost automatically.”