Translation guide
How to express gaining weight in Japanese, from neutral statements to casual and formal expressions.
To state that someone has gained weight, in a neutral or factual way.
Neutral and common way to say body weight increases. Suitable for general statements.
I've gained weight recently.
I'm gaining weight due to lack of exercise.
Common verb meaning 'to get fat/gain weight'. Slightly more direct than 体重が増える, but still widely used in casual conversation.
I ate too much and gained weight.
At this rate, I might gain weight.
More formal or written expression, often used in medical or technical contexts.
The patient's weight is increasing.
To express intentionally gaining weight, e.g., for health or sports.
Casual or colloquial ways to say someone has gained weight.
Casual contraction of 太ってしまった, implying 'I ended up gaining weight' with a nuance of regret or unintended result.
I've put on weight lately.
Describes a pleasantly plump or chubby appearance, often used for people or animals. Not necessarily negative.
She's gotten a bit chubby.
Slang verb from デブ (fatty), meaning 'to get fat'. Can be self-deprecating or insulting; use with caution.
Can be offensive. Only use in very informal settings with close friends.
Polite or formal expressions for gaining weight, suitable for professional or respectful contexts.
While 太る is common, it directly means 'get fat' and can sound blunt. In sensitive situations, prefer 体重が増える or soften with ～ちゃった.
Did you gain a little weight?
体重が増える is intransitive (weight increases by itself), while 体重を増やす is transitive (someone intentionally increases weight). Use the latter when describing deliberate weight gain.
I've gained 5 kilograms.
She gained weight after quitting sports.
I got fat again.