Translation guide
To express that something happens quickly and unexpectedly, Japanese uses adjectives like 突然の, adverbs like 突然 or いきなり, and verbs like 急に. The best choice depends on whether you are describing a noun, an action, or a change, and how formal or casual the situation is.
To say that something happens suddenly, without warning, or all at once.
The most common and neutral way to say 'suddenly'. Works in both spoken and written Japanese. Can be used for events, actions, and changes.
突然、雨が降り出した。
Suddenly, it started raining.
彼は突然部屋を出て行った。
He suddenly left the room.
Very common in casual speech. Emphasizes the abruptness or quickness of a change. Slightly more conversational than 突然.
急にお腹が痛くなった。
My stomach suddenly started hurting.
急に静かになった。
It suddenly got quiet.
Implies something happening without any prior notice or buildup, often with a nuance of being abrupt or rude. Common in casual conversation.
Can sound negative or imply lack of manners if used for someone's actions. Not suitable for formal writing.
いきなりそんなこと言われても困る。
I don't know what to do if you suddenly say something like that.
彼はいきなり歌い出した。
He suddenly burst into song.
Means 'unexpectedly' or 'all of a sudden'. Often used in literary or formal contexts. Less common in daily speech.
不意にドアが開いた。
The door suddenly opened.
To modify a noun and say that something is sudden or unexpected.
The standard way to say 'a sudden (noun)'. Attach directly before the noun.
突然の訪問ですみません。
Sorry for the sudden visit.
突然の停電で何も見えなくなった。
Because of the sudden blackout, I couldn't see anything.
Used for sudden changes or events, often with a nuance of urgency. Common in daily conversation.
急な用事ができて行けなくなった。
Something sudden came up and I can't go anymore.
Literary or formal adjective meaning 'unexpected'. Used in set phrases like 不意の出来事 (unexpected event).
不意の来客に驚いた。
I was surprised by the unexpected visitor.
To describe a sudden medical event or fatal incident.
The medical/formal term for 'sudden death'.
彼は突然死した。
He died suddenly.
Another term for sudden death, often used in news reports.
Sudden illness. Often used in the phrase 急病で倒れる (collapse from a sudden illness).
To emphasize that something happened completely without warning or reason.
Literally 'one day, suddenly'. Used for life-changing events that happen out of the blue.
ある日突然、彼から連絡が来た。
One day, out of the blue, I heard from him.
Means 'without any warning' or 'without prior notice'. More formal.
地震は前触れなく起こった。
The earthquake happened without any warning.
Emphatic version of 前触れなく: 'without the slightest warning'.
何の前触れもなく彼は姿を消した。
He disappeared without the slightest warning.
突然 (totsuzen) is the most neutral and can be used in any situation. 急に (kyuu ni) feels more conversational and emphasizes the speed of change. いきなり (ikinari) implies a lack of warning and can carry a negative nuance of abruptness or rudeness. Use 突然 for formal writing, 急に for casual speech about changes, and いきなり when someone does something without any prior indication.
突然の雨で濡れた。
I got wet from the sudden rain.
急に寒くなったね。
It suddenly got cold, huh?
いきなり怒鳴られてびっくりした。
I was shocked when he suddenly yelled at me.
While 突然の is correct, learners sometimes try to use 突然 directly before a noun without の, which is ungrammatical. Always use 突然の + noun.
突然の知らせ
sudden news
突然、電気が消えた。
All of a sudden, the lights went out.
彼は急な決断をした。
He made a sudden decision.
いきなり現れないでよ！
Don't just show up out of nowhere!
A famous actor died suddenly.
急病で入院した。
I was hospitalized due to a sudden illness.