Translation guide
The English verb "join" covers many distinct actions: becoming a member, physically connecting things, participating in an activity, meeting someone, or combining forces. Japanese uses different words for each meaning. Translating "join" directly often leads to unnatural Japanese.
To become a member of an organization, group, club, or team.
The most common and natural way to say "join" a group, club, company, or organization. Use the particle に.
来月、テニスクラブに入ります。
I'm going to join the tennis club next month.
彼は去年、会社に入った。
He joined the company last year.
More formal than 入る. Often used for joining events, conferences, or projects. Implies participation rather than just membership.
会議に参加しますか？
Will you join the meeting?
Formal term for joining an organization, insurance, or a system. Often used in official contexts.
保険に加入する必要があります。
You need to join an insurance plan.
To connect two or more things together, such as pipes, wires, or pieces of material.
General verb for connecting things physically or abstractly (e.g., joining hands, linking computers).
このパイプをつないでください。
Please join these pipes together.
手をつないで歩こう。
Let's walk holding hands (joining hands).
Technical term for connecting devices, networks, or transport links. Common in IT and engineering.
Wi-Fiに接続してください。
Please join the Wi-Fi network.
Formal or technical term for joining or combining elements into a single unit, often used in chemistry, mathematics, or engineering.
これらの部品を結合します。
We join these parts together.
To take part in an activity, game, or conversation that is already in progress.
The standard verb for joining an activity, event, or discussion. Use に.
ゲームに参加してもいい？
Can I join the game?
会話に参加したいです。
I'd like to join the conversation.
Similar to 参加する but slightly more casual and often used for joining a group or activity spontaneously. Intransitive verb.
私たちのチームに加わらない？
Why don't you join our team?
Very casual way to ask to join in, especially among friends or children. Literally "let me mix in."
ねえ、私も混ぜて！
Hey, let me join in too!
To go with someone or meet them at a place, often for a shared activity.
Used when you join someone at a location after they have already arrived or started. Implies meeting up with a group.
後で合流しましょう。
Let's join up later.
駅で友達と合流した。
I joined my friends at the station.
Literally "go together." Natural way to say you will join someone in going somewhere.
買い物に一緒に行かない？
Won't you join me for shopping?
Formal term for accompanying someone, often used in business contexts.
部長に同行して大阪へ行きます。
I will join the department head on a trip to Osaka.
To combine two or more things into a single entity, such as organizations, lists, or efforts.
Used for mergers of companies, organizations, or municipalities.
二つの会社が合併した。
The two companies joined (merged).
To combine or put together, often used for joining forces, efforts, or money.
力を合わせて頑張ろう。
Let's join forces and do our best.
Formal term for integration or unification, often used in IT or organizational restructuring.
システムを統合する計画です。
We plan to join (integrate) the systems.
English "join" is highly polysemous. Using a single Japanese word for all situations will sound unnatural. Always identify the specific meaning first.
入る (はいる) is for becoming a member of a group or entering a physical space. 参加する (さんかする) is for participating in an activity or event. You 入る a club, but you 参加する a meeting.
会社に入る
join a company (as an employee)
プロジェクトに参加する
join a project (participate)