Translation guide
The English word 'confidential' describes information that is meant to be kept secret or private. In Japanese, the most common equivalent is 秘密 (himitsu), but depending on context, other terms like 機密 (kimitsu) for official secrets or 内緒 (naisho) for personal secrets are used. This guide covers how to express confidentiality naturally in Japanese.
Describing information that is not to be shared with others, in everyday or personal contexts.
The most common and versatile word for 'secret' or 'confidential'. Can be used as a noun or na-adjective.
これは秘密です。
This is confidential.
秘密の情報を共有しないでください。
Please do not share confidential information.
Implies a personal secret, often used among friends or family. More casual than 秘密.
これは内緒だよ。
This is confidential, okay? (between us)
Literally 'outside-party confidential'. Used on documents to indicate they are not for external distribution.
この書類は部外秘です。
This document is confidential (not for outsiders).
Referring to classified or proprietary information in government, business, or military contexts.
Used for official secrets, such as state secrets or corporate trade secrets. Often appears in compounds like 機密情報 (classified information).
その情報は機密扱いです。
That information is treated as confidential.
機密文書を厳重に管理してください。
Please strictly manage confidential documents.
Specifically 'trade secret' or 'corporate confidentiality'.
A prefix or suffix meaning 'secret' or 'confidential', often seen in stamps or labels like マル秘 (maruhi).
このファイルはマル秘です。
This file is confidential (marked as secret).
Expressing the obligation to keep information confidential, often in legal or business agreements.
Refers to the duty of confidentiality, commonly used in contracts and professional ethics.
守秘義務があります。
I have a duty of confidentiality.
守秘義務契約にサインしました。
I signed a confidentiality agreement.
How to say 'keep confidential' or 'maintain secrecy' in Japanese.
The most common way to say 'keep something secret/confidential'.
このことは秘密にしてください。
Please keep this confidential.
Casual version of 'keep secret', used among close acquaintances.
これは内緒にしておいてね。
Keep this confidential, okay?
A formal, technical verb meaning 'to conceal' or 'to keep confidential', often used in IT or legal contexts.
個人情報を秘匿する必要があります。
We need to keep personal information confidential.
秘密 (himitsu) is the general term for 'secret' and can be used in most situations. 内緒 (naisho) is more personal and casual, implying a secret between individuals. 機密 (kimitsu) is reserved for official, corporate, or military secrets and carries a formal tone.
これは私たちだけの内緒だよ。
This is just between us (confidential).
国家機密に関わる情報です。
It's information related to state secrets.
Avoid directly translating 'confidential' as コンフィデンシャル (konfidensharu) in most contexts. While understood in some business settings, it sounds unnatural. Use the appropriate Japanese term based on context.
これは企業秘密です。
This is a trade secret.
The formal term for a non-disclosure agreement (NDA).
秘密保持契約を結びましょう。
Let's sign a confidentiality agreement.