Rok vraćanja je danas.

In this sentence, rok means deadline, time limit, or due date.

So rok vraćanja means something like:

• the return deadline
• the due date for returning
• the deadline for giving something back

Serbian rok is very commonly used for deadlines:

• rok plaćanja = payment deadline
• rok isporuke = delivery deadline
• krajnji rok = final deadline

Because vraćanja is in the genitive case.

The base form is vraćanje, which is a verbal noun meaning returning or the act of returning. After rok, Serbian often uses a noun in the genitive to mean the deadline of/for something.

So:

• vraćanje = returning
• vraćanja = of returning / for returning

That is why:

• rok vraćanja = deadline for returning

This pattern is very common in Serbian:

• vreme polaska = departure time
• mesto sastanka = meeting place
• datum rođenja = date of birth

Vraćanje is a verbal noun formed from the verb vraćati / vratiti.

It means:

• returning
• giving back
• sometimes coming back, depending on context

In this sentence, it most likely means returning an item, such as a book, library material, rental object, and so on.

So rok vraćanja would often be used in contexts like:

• library books
• borrowed items
• rented equipment

Je is the 3rd person singular present tense of biti (to be), so it means is.

The sentence structure is:

• Rok vraćanja = the return deadline
• je = is
• danas = today

So literally:

• The return deadline is today.

In standard Serbian, this is the normal way to link the subject and the predicate.

Because danas is an adverb, not a noun.

It means today, and adverbs do not change for case, number, or gender the way nouns and adjectives do.

So danas stays danas regardless of where it appears in the sentence:

• Danas idem u grad. = I’m going to town today.
• Sastanak je danas. = The meeting is today.
• Rok vraćanja je danas. = The return deadline is today.

Yes, absolutely. Danas je rok vraćanja is also natural.

The difference is mainly emphasis:

• Rok vraćanja je danas.
  Focuses first on the return deadline.
• Danas je rok vraćanja.
  Focuses first on today.

Serbian word order is more flexible than English word order, so moving elements around often changes emphasis rather than basic meaning.

Yes. Rok za vraćanje is also correct and natural.

Compare:

• rok vraćanja
• rok za vraćanje

Both mean deadline for returning.

The version without za is a bit more compact and often sounds slightly more formal or administrative. The version with za can feel a little more transparent to learners because it matches English for returning more closely.

You will see both patterns in Serbian.

Usually it means the deadline, not necessarily the day when the item will in fact be returned.

That is an important distinction.

• rok vraćanja = the date by which something must be returned
• datum vraćanja = the return date, which can mean the scheduled or actual date of return depending on context

So if a library says Rok vraćanja je danas, it means you must return it today at the latest.

A rough pronunciation is:

VRA-cha-nya

A few notes:

• ć is a soft sound, somewhat like a softer ch
• nj is pronounced like the ny in canyon
• the j in Serbian is like English y

So:

• vra-ća-nja
• roughly VRA-cha-nya

Yes, it is completely natural and correct.

It sounds like something you might see or hear in places such as:

• a library
• a rental service
• a school
• an office notice
• an online account page

It is short, clear, and standard Serbian.