Translation guide
Describing a person, statement, or thing that cannot be relied on as honest or true. Japanese has many nuanced words for untrustworthiness, ranging from suspicious character to outright dangerous.
Describing a person who cannot be trusted, is suspicious, or unreliable.
The most common and versatile word. Means suspicious, shady, dubious. Can describe a person, situation, or thing.
That person is a bit untrustworthy.
Be careful of suspicious solicitations.
Literally 'cannot trust'. A direct and clear way to say someone is untrustworthy.
He is untrustworthy.
That information is unreliable.
Stronger than 怪しい, implies something smells fishy or is clearly dubious. Often used for people or deals.
That salesman is untrustworthy/shady.
Means unreliable, undependable. Focuses on not being able to count on someone.
He's untrustworthy, so I can't entrust him with important work.
Literally 'dangerous'. Can imply a person is untrustworthy in a risky or threatening way.
That man is untrustworthy/dangerous, so you'd better stay away.
Describing information, stories, or claims that are not reliable or likely false.
Means unreliable, not to be counted on. Commonly used for information, rumors, or predictions.
What he says is untrustworthy.
Weather forecasts can be unreliable.
Means uncertain, unreliable. Slightly formal, often used for information or memories.
Describing a look, atmosphere, or gut feeling that something is not right.
Means shady, disreputable, often implying something indecent or not proper. Used for businesses, people, or content.
You shouldn't go into untrustworthy/shady shops.
Same as 胡散臭い, but in kana. Very common in speech for a fishy feeling.
怪しい is more about a gut feeling of suspicion, while 信用できない is a direct statement of lack of trust. 怪しい can be used lightly, but 信用できない is a serious judgment.
That person seems suspicious, but it's too early to decide they're untrustworthy.
There is no single Japanese adjective that perfectly matches 'untrustworthy' in all contexts. Avoid direct translations like 信頼できない (which is closer to 'unreliable' for objects) when describing a person's character; use 信用できない instead.
その情報は不確かだ。
That information is untrustworthy.
Means doubtful, questionable. Implies there is reason to suspect falsehood.
His testimony is untrustworthy.
That sounds like an untrustworthy story.