Learn Hardcore Czech: Chci se podívat do kalendáře.

podívat se (na / do něčeho) = to have a look (at / in something), to take a look
You normally use this verb with "se"; without it (podívat) it sounds incomplete or wrong in this meaning.

So you can think of podívat se as one unit, like an idiomatic verb “to have a look”.
You don’t translate "se" directly into English here; it’s just required by the Czech verb pattern.

What is the difference between "dívat se" and "podívat se"?

These two verbs form an aspect pair (imperfective vs. perfective):

dívat se – imperfective: to look / to be looking (focus on the process, duration)
- E.g. Dívám se na film. – I am watching a movie.
podívat se – perfective: to have a look (focus on a single, complete act)
- E.g. Chci se podívat do kalendáře. – I want to have a (quick) look in the calendar.

In your sentence, you want to check the calendar once, not watch it continuously, so podívat se (perfective) is the natural choice.

You can’t normally replace podívat se with dívat se in this sentence without changing the nuance:

Chci se dívat do kalendáře sounds like I want to be looking in the calendar (for a while), which is unusual here.

Why is it "Chci se podívat" and not something like "Chci se podívám"?

In Czech, the verb chtít (to want) is followed by the infinitive of the other verb, just like in English:

English: I want to look
Czech: Chci se podívat

So the structure is:

chci (I want) + se podívat (to have a look)

You cannot use a finite verb (like podívám) after chtít in this meaning:

✗ Chci se podívám do kalendáře. – incorrect
✓ Chci se podívat do kalendáře. – correct

Can I change the word order? For example, is "Chci podívat se do kalendáře" correct?

The natural word order here is:

Chci se podívat do kalendáře.

The little word "se" is a clitic; in Czech it tends to stay near the beginning of the clause, usually after the first stressed word. So some orders are grammatical but sound odd or marked.

Let’s evaluate some variants:

✓ Chci se podívat do kalendáře. – normal, neutral.
✗ Chci podívat se do kalendáře. – sounds wrong; "se" is in a bad position.
✓ Chci se do kalendáře podívat. – possible; slightly different emphasis.
? Se chci podívat do kalendáře. – can occur in spoken language for emphasis (Emphatic: “I do want to look in the calendar”), but not the default learner pattern.

As a learner, stick to:

Chci se podívat do kalendáře.

Why is it "do kalendáře" and not "na kalendář"?

Both "do" and "na" can appear with verbs of looking, but they have different typical uses and images.

do + GENITIVE often suggests looking into something, as into its contents:
- do kalendáře – into the calendar (to check dates, entries)
- do knihy – into a book
- do tašky – into the bag
na + ACCUSATIVE often suggests looking at a surface or toward something:
- na obraz – at the picture
- na televizi – at the TV
- na hodiny – at the clock

So:

Chci se podívat do kalendáře.
→ I want to look in the calendar (to check something inside it).

If you said:

Chci se podívat na kalendář.
it would sound more like you want to look at the calendar as an object (e.g., to see its design), not really to check the dates.

What case is "kalendáře", and why does it change from "kalendář"?

Kalendář is the base form (nominative singular).

After the preposition do, Czech uses the genitive case, so you need the genitive form:

do + genitive
do kalendáře

So:

Nominative: kalendář – a calendar (subject form)
Genitive (singular): kalendáře – of a calendar / into a calendar

This pattern is standard:

do domu – into the house (dům → domu)
do auta – into the car (auto → auta)
do kalendáře – into the calendar (kalendář → kalendáře)

Is there a more colloquial way to say "Chci se podívat do kalendáře"?

Yes. A very common colloquial verb is kouknout se or mrknout se:

Chci se kouknout do kalendáře.
Chci se mrknout do kalendáře.

Both mean roughly: I want to take a look in the calendar, but they are informal and common in spoken Czech.

Neutral / standard:

Chci se podívat do kalendáře.

Colloquial:

Chci se kouknout do kalendáře.
Chci se mrknout do kalendáře.

How do I say this more politely, for example in a formal situation?

To be more polite or softer in Czech, you usually use the conditional of chtít:

For a man:

Chtěl bych se podívat do kalendáře.

For a woman:

Chtěla bych se podívat do kalendáře.

This corresponds to something like:

I would like to have a look at the calendar.

So:

Chci se podívat… – neutral, direct: I want to…
Chtěl/Chtěla bych se podívat… – more polite/softened: I would like to…

Does "Chci se podívat do kalendáře" mean a physical paper calendar, or can it also mean my phone calendar / schedule?

Literally, kalendář is a calendar (wall calendar, desk calendar, etc.). But in context, it can also refer to:

a digital calendar:
Chci se podívat do kalendáře v telefonu. – I want to look in the calendar on my phone.
a schedule/diary, though for that diář or kalendář v diáři is more precise.

If someone says:

Podívám se do kalendáře.
in everyday conversation, it can easily mean I’ll check my calendar (whatever form it is), not necessarily a paper one. Context usually makes it clear.

How is the sentence pronounced, and where is the stress?

The sentence is:

Chci se podívat do kalendáře.

Pronunciation (approximate, in English-friendly terms):

Chci – [xʦi]
- ch = a voiceless kh sound, like in German Bach.
- c = ts.
- So it’s roughly khtsi in one syllable.
se – [se] (like “seh”)
podívat – [poˈdiːvat]
- podí- = po-dee (with long í), stress on dí.
do – [do] (like English “dough” but shorter)
kalendáře – [kalɛnˈdaːr̝ɛ]
- kal-en-DA-ře, with stress on DA.
- ř is a special Czech sound: a rolled/trilled r combined with ž; hard for learners, but you can approximate with rzh at first.

Stress in Czech is almost always on the first syllable of each word:

CHCI se PO-dí-vat DO ka-len-DÁ-ře.

All words are pronounced clearly; there is no reduced vowel like English schwa in unstressed syllables.