Formal:
* मैं ठीक हूँ (main theek hoon): This is the most common and literal translation, meaning "I am well". It's suitable for most situations.
* मैं स्वस्थ हूँ (main swasth hoon): This means "I am healthy" and implies a good state of physical well-being.
Informal:
* मैं ठीक हूँ (main theek hoon): This is still acceptable in informal settings.
* मैं सही हूँ (main sahi hoon): This means "I am alright" and can be used in casual conversations.
* मैं अच्छा हूँ (main achcha hoon): This translates to "I am good" and is often used in everyday speech.
For answering "How are you?":
* मैं ठीक हूँ (main theek hoon) is the most common response.
* बहुत अच्छा (bahut accha) means "Very good" and is a more enthusiastic response.
Remember that the best way to say "I am fine" in Hindi will depend on the context and your relationship with the person you're talking to.