How to say "roger" in Japanese

• ラジャ
  interjectionA borrowing of the English word itself, used as a quick acknowledgment meaning 'understood' or 'OK'; it is much less common than 了解 and tends to appear in radio-style or playful exchanges.
• りょ
  interjectionInternet slang: an abbreviation of 了解 used in online chats as a very short 'understood' or 'OK'; it is less common and belongs to casual online writing rather than formal prose.
• 合点承知之助がってんしょうちのすけ
  expressionA colloquial set phrase shaped like a person's name, meaning 'got it — leave it to me'; as 'roger' it carries a playful, wholehearted tone, so it is seldom the neutral acknowledgment you want.
• がってんだ
  expressionAn exclamation meaning 'understood', 'all right', or 'got it'; usually written in kana and akin to 合点承知之助, it works as a hearty 'roger' but is a less common choice.
• 了解りょうかいJLPT N1approx.Common
  interjectionThe common, all-purpose word: use it to acknowledge an instruction, request, or message with a simple 'OK' or 'roger'; when in doubt, this is the word to reach for.
  「とりあえず店みせの前まえ、掃除そうじしといてくれ」「了解りょうかい！」「打ち水うちみずも頼たのむ」↗

  "Clean up in front of the shop first." "OK!" "Sprinkle some water out there too."

For the everyday 'roger' of acknowledging an instruction, use 了解; 「ラジャ」 echoes the English word itself, 「りょ」 is internet slang, and 合点承知之助 and 「がってんだ」 are colorful 'got it' exclamations.

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

• ラジャroger
• りょunderstood
• 合点承知之助がってんしょうちのすけgot it
• がってんだunderstood
• 了解りょうかいOK