Не может быть!

Literally, it means It cannot be! or That can’t be!

Word by word:

• не = not
• может = can / is able to
• быть = to be

So the structure is basically [It] cannot be. In natural English, it often corresponds to No way!, That can’t be!, or Impossible!, depending on context and tone.

Russian often leaves out subjects when they are obvious from context or when the sentence is used as a general reaction.

In English, you usually need something like it or that:

• It can’t be
• That can’t be

In Russian, Не может быть! works perfectly without an explicit subject. The missing idea is understood from the situation: this / that / it.

This is very normal in Russian, especially in short emotional expressions.

Может is the 3rd person singular form of мочь (to be able, can).

Compare:

• я могу = I can
• ты можешь = you can
• он/она/оно может = he/she/it can

Since the sentence means it can’t be or that can’t be, Russian uses the 3rd person singular form: может.

Even though the subject is not spoken, the verb still shows what kind of subject is understood.

Because after мочь (can / be able to), Russian normally uses an infinitive.

So:

• может быть = can be
• не может быть = cannot be

This is similar to English:

• can be
• cannot be

Here, может is the finite verb, and быть stays in the basic dictionary form, the infinitive: to be.

Yes, может быть can also mean maybe in some contexts.

For example:

• Может быть, он придёт. = Maybe he’ll come.

But Не может быть! is different. Here it is not the expression maybe. It is the verb phrase cannot be.

You can tell from:

1. the не
2. the exclamation
3. the context and intonation

So:

• может быть = can be or maybe
• не может быть! = that can’t be! / no way!

It is a very common reaction to surprising, shocking, or unbelievable information.

It can express:

• disbelief
• surprise
• amazement
• mild shock

For example, if someone says:

• Я выиграл миллион. = I won a million.

A natural reaction could be:

• Не может быть! = No way! / That can’t be!

Depending on tone, it can sound:

• genuinely shocked
• delightedly surprised
• skeptical
• dramatic

So it is not always cold logical disbelief; it is often emotional.

It is neutral and very common. You can hear it in everyday speech, movies, books, and conversation.

It is not slang, but it is also not especially formal. It works well in most normal spoken situations.

If you want something more formal or bookish, you might say something like:

• Это невозможно. = That is impossible.

But Не может быть! sounds more like a natural spontaneous reaction.

Both can express that something is impossible, but they feel a little different.

Не может быть!

• more conversational
• more emotional
• often a spontaneous reaction
• often means No way! or That can’t be!

Это невозможно!

• more direct and literal
• can sound more formal or more firm
• often means That is impossible

For example:

• hearing surprising gossip: Не может быть!
• rejecting a plan as unworkable: Это невозможно!

So Не может быть! is often about disbelief, while Это невозможно! is often about impossibility.

The stress is:

• не мОжет быть

More precisely:

• не = nye
• мОжет = stress on the first syllable
• быть = a short word with a final soft consonant

A rough pronunciation guide:

• nye MO-zhet byt'

A few points:

• не is usually pronounced close to nye
• ж sounds like the s in measure
• ть at the end of быть is soft

In emotional speech, intonation matters a lot. People often strongly stress мОжет or say the whole phrase with rising-falling surprise.

Yes, very easily.

Like many expressions of surprise in both Russian and English, Не может быть! can be sincere or sarcastic depending on tone.

For example, if someone says something completely obvious, a speaker might say Не может быть! in a sarcastic way, like English Really? No way.

So tone of voice is crucial.

Sometimes yes, but not always.

Possible translations include:

• That can’t be!
• It can’t be!
• No way!
• Impossible!

The best choice depends on context.

Use Impossible! when the tone is strong and dramatic.

Use No way! when the tone is more conversational and emotional.

Use That can’t be! when you want the closest structural match to the Russian.

So Impossible! is possible, but it is just one option, not the only one.