Tớ rảnh.

Tớ is a casual way to say I / me. It is commonly used with friends, classmates, people your age, or someone you are close to.

It sounds:

• friendly
• informal
• natural in casual conversation

You should usually not use tớ with:

• your boss
• much older people
• strangers in formal situations

A very common pair is tớ - cậu for I - you between friends.

In Tớ rảnh, rảnh works like an adjective, meaning something like free, not busy, or available.

Vietnamese adjectives can often act like the main predicate of a sentence, so you do not need a separate word for am/is/are.

So the structure is basically:

• Tớ = I
• rảnh = free / not busy

Vietnamese usually does not use a verb like English to be in sentences like this.

English says:

• I am free

Vietnamese simply says:

• Tớ rảnh

This is very normal. When describing a person or thing with an adjective, Vietnamese often just puts:

subject + adjective

For example:

• Tớ mệt. = I’m tired.
• Tớ vui. = I’m happy.
• Tớ rảnh. = I’m free.

It can mean both, depending on context.

Rảnh often suggests:

• you are not busy
• you have free time
• you are available

For example:

• Chiều nay tớ rảnh. = I’m free this afternoon.
• Cậu có rảnh không? = Are you free / available?

So rảnh is often about time and schedule, not just freedom in a broad sense.

Yes, Tớ rảnh is casual.

Other possibilities depend on who you are speaking to:

• Tôi rảnh. → more neutral or formal
• Mình rảnh. → friendly, soft, often casual
• Em rảnh. → if you refer to yourself as em
• Anh rảnh. / Chị rảnh. → if you refer to yourself that way

Vietnamese pronouns change a lot depending on relationship, age, and situation. The word rảnh stays the same, but the pronoun may change.

Yes, in conversation you often can.

Vietnamese frequently drops the subject when it is already obvious from context. So if someone asks you something like:

• Đi cà phê không? = Want to go for coffee?

You might simply reply:

• Rảnh. = I’m free.
• Không rảnh. = I’m not free.

This is natural in spoken Vietnamese, especially in casual situations.

A rough pronunciation guide is:

• tớ: starts with t, then a vowel somewhat like ơ, with a rising tone
• rảnh: starts with r, ends with nh like the ny sound in canyon, with a dipping-then-rising tone

A few useful notes:

• ớ has the sắc tone
• ảnh has the hỏi tone
• tones are very important in Vietnamese

Also, pronunciation of r varies by region:

• in the North, it may sound more like z
• in the South, it may sound more like an r

So depending on the speaker, rảnh may sound a bit different.

You usually put không before rảnh:

• Tớ không rảnh. = I’m not free.

You may also hear:

• Tớ bận. = I’m busy.

Both are natural, but the nuance is slightly different:

• không rảnh = not free
• bận = busy

A very common way is to add không at the end:

• Cậu rảnh không? = Are you free?

You can also ask about yourself in some contexts, but usually you ask another person.

Other natural examples:

• Chiều nay cậu rảnh không? = Are you free this afternoon?
• Lúc nào cậu rảnh? = When are you free?

In casual speech, intonation also helps show that it is a question.

Yes. Tớ has a warm, personal, and youthful feel. It often sounds:

• close
• casual
• equal

It is especially common in friendly conversations, and often pairs naturally with cậu.

Compare:

• Tớ rảnh. → casual, friendly
• Tôi rảnh. → more neutral or formal
• Mình rảnh. → friendly, softer, sometimes more intimate

So the sentence is not just about grammar; it also shows the relationship between speakers.