Translation guide
Describes behavior or a person that lacks thought for others' feelings or needs. Japanese often uses specific phrases rather than a single adjective.
Describing someone's action or attitude as thoughtless or selfish.
Literally 'lacks compassion/consideration'. The most common and natural way to say someone is inconsiderate.
He is really inconsiderate.
Saying something like that is so inconsiderate.
Means 'insensitive' or 'thoughtless'. Often used for blunt or tactless remarks.
I was hurt by his inconsiderate remark.
Literally 'not perceptive/attentive'. Used when someone fails to notice what needs to be done or how others feel.
He's so inconsiderate, he doesn't even offer to help.
Means 'selfish' or 'self-centered'. Stronger than 'inconsiderate', implying willful disregard.
Stop being so inconsiderate (selfish).
Formal expression meaning 'lacking consideration'. Used in written or formal contexts.
The plan is inconsiderate of the residents.
Pointing out a particular act as thoughtless or rude.
思いやりがない is a general lack of consideration for others' feelings. 無神経 specifically points to insensitivity or tactlessness, often in speech.
He is inconsiderate (in general).
He is insensitive/tactless.
There is no single Japanese adjective that perfectly matches 'inconsiderate'. Using a dictionary word like 無分別 (mufunbetsu) may sound unnatural or archaic. Stick to the phrases above.
It was inconsiderate of him to cancel at the last minute.
Don't be so inconsiderate!
It's inconsiderate to vacuum in the middle of the night.