Ez a kártyaszám.

Ez means this.

In this sentence, it points to something near the speaker, just like English this. Hungarian has a basic contrast:

• ez = this
• az = that

So Ez a kártyaszám. starts with this.

This is a very common Hungarian pattern.

When a demonstrative like ez or az comes before a noun, Hungarian normally also keeps the definite article:

• ez a könyv = this book
• az a ház = that house
• ez a kártyaszám = this card number / this is the card number

So ez a is not redundant in Hungarian. It is the normal structure.

A useful way to remember it is:

• ez = points to the thing
• a = the definite article that still stays with the noun

Because in Hungarian, the verb to be is often omitted in the present tense, in the third person, when the sentence links two nouns or a noun and an adjective.

So English:

• This is the card number.

Hungarian:

• Ez a kártyaszám.

There is no separate is here.

Compare:

• Én fáradt vagyok. = I am tired.
• Te fáradt vagy. = You are tired.
• Ő fáradt. = He/she is tired.
  → no word for is

The same idea works here: Ez a kártyaszám.

Kártyaszám is a compound noun. It is made from:

• kártya = card
• szám = number

So literally it means card number.

Hungarian forms compounds very freely, much more often than English. Instead of writing two separate words, Hungarian often combines them into one word.

So:

• kártyaszám = card number

Depending on context, it could mean something like a bank card number, ID card number, or another kind of card number.

A simple pronunciation guide:

• Ez ≈ ez in English bed, but with a clear z
• a = a short open vowel, roughly like o in some pronunciations of hot, but not exactly
• kártya ≈ KAAR-tyaw
• szám ≈ saam

A few key pronunciation points:

• Hungarian stress is almost always on the first syllable of each word.
  • EZ
  • a
  • KÁR-tya-szám
• á is a long vowel.
• sz is pronounced like English s.
• A plain Hungarian s is pronounced like English sh, but there is no plain s here by itself; in szám, the sz is just s.

A rough full pronunciation is:

EZ a KAAR-tya-saam

Hungarian has two forms of the definite article:

• a
• az

The choice depends on the next sound:

• a before a consonant
• az before a vowel

Since kártyaszám begins with k, a consonant, the correct form is a:

• a kártyaszám

Compare:

• az alma = the apple
• a könyv = the book

So here, ez a kártyaszám is correct.

Yes. Hungarian very often writes noun + noun combinations as a single compound word.

That is why kártya + szám becomes:

• kártyaszám

This is very normal in Hungarian. English often leaves such expressions as two words, but Hungarian frequently joins them.

Other similar examples:

• telefonszám = telephone number
• házszám = house number
• bankszámla = bank account

So a learner should get used to seeing many meanings packed into one written word.

Yes, but this sentence uses a very normal and neutral order.

• Ez a kártyaszám.

This is the most straightforward way to say This is the card number.

Hungarian word order is more flexible than English, but changes often affect emphasis or topic-focus structure. So while another order may be possible in a special context, the version you have is the standard one a learner should use.

In other words:

• Ez a kártyaszám. = neutral, natural
• other orders may sound marked, contrastive, or context-dependent

By itself, with a full stop, it is normally understood as a complete sentence: This is the card number.

If Hungarian wanted just the noun phrase this card number, it would still look like ez a kártyaszám in form, but the surrounding context would show that it is only a phrase and not a full sentence.

So the same words can function as:

• a noun phrase: this card number
• a full sentence: this is the card number

In your example, since it stands alone as a sentence, learners will usually understand it as This is the card number.

Yes. When Hungarian demonstratives take case endings, they change quite a lot.

For example:

• ez = this
• ebben = in this
• ezt = this, as an object

And with a noun, Hungarian often shows the case ending on both the demonstrative and the noun:

• ebben a házban = in this house
• ezt a könyvet = this book

That is a bigger grammar pattern, but it is useful to know early because ez a ... is just the basic dictionary-like form.