Sada mi je bolje.

• Sada = now
• mi = to me / for me (short dative form of ja)
• je = is (3rd person singular of biti, to be)
• bolje = better

Literally, the structure is closer to Now it is better to me, which Serbian uses for the idea I feel better now or I’m better now.

Because Serbian does not express this idea the same way English does.

In English, you say I am better with I as the subject.
In Serbian, this expression is usually built more like It is better to me:

• meni je bolje = I feel better / it’s better for me
• short form: mi je bolje

So mi is not the subject. It is a dative pronoun meaning to me / for me.

Mi is the dative singular form of ja.

Here are the relevant forms:

• ja = I (nominative)
• mene / me = me (accusative/genitive)
• meni / mi = to me / for me (dative)

In Sada mi je bolje, Serbian uses the dative because the idea is about someone’s state or experience: it is better to me / for me.

This is one of the most common learner questions.

Even though the English translation is I am better, Serbian is not literally saying I am better with ja sam. Instead, it uses an impersonal-type structure:

• meni je bolje = it is better to me

That is why the verb appears as je (is), not sam (am).

Compare:

• Ja sam umoran. = I am tired.
• Meni je bolje. = I feel better.

So this sentence does not have ja as the grammatical subject.

Bolje is the comparative form meaning better.

It comes from dobro / dobar:

• dobar = good (adjective)
• dobro = well / good
• bolji = better (adjective)
• bolje = better (adverb or neuter comparative form used in expressions like this)

In mi je bolje, bolje is the normal form used for how someone feels.

Compare:

• On je bolji čovek. = He is a better man.
  
  • Here bolji agrees with čovek.
• Meni je bolje. = I feel better.
  
  • Here bolje is the natural form in this expression.

Not really in the way an English speaker might expect.

English learners often look for the hidden ja, but this sentence does not work like Ja sam bolje in standard Serbian. The construction is centered around the experiencer in the dative:

• meni/mi = the person affected
• je bolje = is better

So the sentence is best understood as a set expression meaning it is better for me / I feel better, rather than a sentence with an omitted I subject.

Serbian word order is flexible, but mi and je are clitics. Clitics are short unstressed words that usually go near the beginning of the sentence, often in second position.

That is why:

• Sada mi je bolje. sounds natural.

Here, Sada takes the first position, and then the clitic cluster mi je comes right after it.

Other possible orders can exist for emphasis, for example:

• Mi je sada bolje. — generally not acceptable as a neutral sentence because clitics usually do not start the sentence.
• Sada je meni bolje. — possible, but more emphatic on meni
• Bolje mi je sada. — also natural

So the given order is a very normal, neutral one.

Normally, no.

Mi and je are clitics, and clitics usually cannot stand at the very beginning of a sentence.

So:

• Mi je bolje. = generally not acceptable as a neutral standalone sentence
• Bolje mi je. = natural
• Sada mi je bolje. = natural

Serbian typically needs some stressed word before the clitics.

In standard Serbian, Sada mi je bolje is the more natural and preferred way to express this meaning.

You may hear forms like Bolje sam in casual speech, but for learners, it is much safer to use:

• Bolje mi je.
• Sada mi je bolje.

That is the normal and idiomatic pattern.

Both mean now.

• sada = full form
• sad = shorter, very common in everyday speech

So these are both natural:

• Sada mi je bolje.
• Sad mi je bolje.

The difference is mainly style and rhythm, not meaning.

Yes.

• meni = full form
• mi = short clitic form

Both are correct, but they are used differently:

• Meni je bolje. = more emphatic, contrastive, or deliberate
• Mi je bolje. = not possible at the beginning by itself because mi is a clitic
• Sada mi je bolje. = natural, because sada comes first
• Sada je meni bolje. = possible, with extra emphasis on meni

If you want a neutral sentence with no emphasis, Sada mi je bolje is excellent.

A simple approximation is:

SA-da mi ye BO-lye

A few notes:

• j in Serbian sounds like English y in yes
• je sounds roughly like ye
• lj in bolje is a single Serbian sound, somewhat like the lli in million for many English speakers

So bolje is not pronounced bol-je with a hard English j. It is closer to BO-lye.

It can be used more broadly.

In Sada mi je bolje, it often means someone feels better physically or emotionally. But bolje can also be used in many other contexts:

• Ovo je bolje. = This is better.
• On radi bolje nego pre. = He works better than before.
• Sad mi je bolje can mean I feel better now, whether physically, emotionally, or generally.

So the exact nuance depends on context.