Translation guide
The English verb "require" covers needs, obligations, and formal demands. In Japanese, the best choice depends on whether you mean something is necessary, a rule or condition demands it, or someone formally requests it.
この仕事は経験を必要とする。
This job requires experience.
ここにサインする必要があります。
You are required to sign here.
Expressing that something is needed or necessary, often in a general or personal sense.
Literally 'to make necessary'. Used when a person, thing, or situation needs something. Common in both spoken and written Japanese.
この仕事は経験を必要とする。
This job requires experience.
Plants require sunlight.
The most common everyday word for 'need'. Used for concrete things. Intransitive, so the needed thing is marked with が.
この書類には印鑑が要ります。
This document requires a seal.
もっと時間が要る。
I need more time. (More time is required.)
An adjective meaning 'is necessary'. Often used in the pattern ～が必要だ.
成功には努力が必要だ。
Success requires effort.
Pattern using the verb 要る. The thing needed is marked with が.
この料理には特別な材料がいる。
This dish requires special ingredients.
Expressing that a rule, law, or situation demands something, often with a sense of compulsion.
Standard pattern for 'must' or 'have to'. Used for obligations imposed by rules or circumstances.
この国では、車を運転するのに免許を取らなければならない。
In this country, you are required to get a license to drive a car.
図書館では静かにしなければならない。
You are required to be quiet in the library.
Literally 'there is a necessity to'. Slightly more formal and objective than ～なければならない.
この問題を解決する必要がある。
We are required to solve this problem.
契約書にサインする必要があります。
You are required to sign the contract.
To make something mandatory, to obligate. Often used in legal or official contexts.
Formal, often written word meaning 'to require' or 'to need'. Used in official documents.
Expressing that someone in authority formally asks or demands something.
To demand, to request firmly. Used when someone with authority or a strong position asks for something.
労働者は賃上げを要求した。
The workers demanded a pay raise. (They required a raise.)
警察は彼にパスポートの提示を要求した。
The police required him to show his passport.
To seek, to ask for, to demand. Can be softer than 要求する, but also used in formal contexts.
To order, to command. Stronger than 'require', used when someone in authority gives an order.
必要 (necessity) is a noun/adjective and sounds more formal or abstract. 要る is a verb used for concrete, everyday needs. 必要 is often used in the pattern ～が必要だ, while 要る is used as ～が要る.
English 'require' is often used in passive constructions like 'is required to'. Japanese does not use a direct passive equivalent naturally. Instead, use patterns like ～なければならない or ～必要がある.
法律は企業に情報開示を義務付けている。
The law requires companies to disclose information.
この手続きには時間を要する。
This procedure requires time.
会社は従業員に高い能力を求める。
The company requires high ability from its employees.
裁判所は彼に出頭を命じた。
The court required him to appear.