During informal conversations with friends and peers, you can use ‘hey’ or ‘yo’, similar to informal English conversations. But you cannot use ‘hey’ or ‘yo’ in informal settings as it doesn’t look professional at all. You should use Konnichiwa (こんにちわ) to say hello, as it can never go wrong.

The most common ways to say “Hello” in Japanese are “Konnichiwa” (こんにちは) throughout the day, “Ohayou Gozaimasu” (おはようございます) in the morning, and “Konbanwa” (こんばんは) in the evening. “A, (name)”, “Yahhoo”, “Osu”, and “Haroo” are casual Japanese greetings that can be used to greet people you know well.

Listen to the link below to hear some informal Japanese greetings… やあ Yā Hi (informal) よう Yō Hey / Yo (informal greeting) 最近どう

With friends, greetings can be more casual: やあ (Yaa): Equivalent to “Hi” or “Hey,” this is very casual. おっす (Ossu): A very informal greeting, often used among young men or close friends.