Translation guide
How to express that an action was done unintentionally, accidentally, or in error.
I did it by mistake.
Casual apology for a careless mistake.
I took the wrong one by mistake.
The action happened without the speaker intending it, often due to carelessness or chance.
Adverb meaning 'carelessly', 'inadvertently'. Used when you do something without thinking or by oversight.
I accidentally missed my train stop.
I carelessly blurted out the secret.
Te-form of 間違う (to make a mistake). Means 'by mistake', 'erroneously'. Used when you do the wrong thing.
Te-form of 誤る (to err). More formal than 間違って. Often used in official contexts or writing.
Adverb meaning 'unintentionally', 'without thinking'. Often used for actions done out of habit or impulse.
Te-form of うっかりする, meaning 'to be careless'. Used to explain the reason for a mistake.
I was careless and forgot the appointment.
The action was done based on a misunderstanding or incorrect information.
Te-form of 勘違いする (to misunderstand). Means 'mistakenly', 'under the wrong impression'.
I went on the wrong day by mistake.
He got angry due to a misunderstanding.
Noun meaning 'misunderstanding', 'wrong idea'. Used with で to mean 'due to a misunderstanding'.
That was a misunderstanding.
The mistake is a physical slip, like dropping something or hitting the wrong key.
うっかり is for careless oversights (forgetting, missing). 間違って is for doing the wrong thing (wrong button, wrong person). 誤って is the formal version of 間違って, used in official apologies or reports.
I carelessly forgot.
I sent it by mistake.
I mistakenly deleted it.
ミスで is a loanword and sounds casual or business-like. It's not natural for personal, everyday mistakes like forgetting an umbrella. Use うっかり or 間違って instead.
Sorry, I opened your mail by mistake.
I accidentally deleted the file.
I pressed the wrong button by mistake.
I took his umbrella home by mistake.
I mistakenly sent personal information.
I ended up eating too much (without meaning to).
I accidentally told a lie.