Kaffið kostar eina krónu minna í dag.

Kaffi means coffee in an indefinite sense, while kaffið means the coffee.

Icelandic usually adds the definite article to the end of the noun instead of using a separate word like English the.

• kaffi = coffee
• kaffið = the coffee

So kaffið kostar... means the coffee costs...

That -ið is the suffixed definite article for a neuter singular noun.

Kaffi is a neuter noun, so when you make it definite in the singular, you get:

• kaffi = coffee
• kaffið = the coffee

This is very typical in Icelandic:

• hús = house
• húsið = the house

Because eina krónu is in the accusative singular.

The verb kosta often takes the price as an object, so the amount being paid appears in the accusative.

Also, króna is a feminine noun, so einn has to agree with it in gender, number, and case.

Here are the relevant forms:

• nominative: ein króna = one króna
• accusative: eina krónu = one króna

So in this sentence:

• Kaffið kostar eina krónu... literally: The coffee costs one króna...

Usually yes, in a sentence like this.

Kostar is the 3rd person singular present tense of kosta:

• ég kosta is not used here because the subject is not I
• það kostar = it costs
• kaffið kostar = the coffee costs

So kostar means costs or is priced at in this context.

Because the sentence is expressing a difference in amount, not just saying that something is generally cheaper.

eina krónu minna means one króna less.

So the structure is:

• amount + minna = less by that amount

Examples:

• tíu krónur minna = ten krónur less
• eina krónu minna = one króna less

If you wanted to say something is cheaper in a more general comparison, you might use ódýrara instead, depending on the sentence.

Here minna is the comparative form meaning less, and it is being used adverbially.

In this sentence it modifies the idea of price:

• kostar eina krónu minna = costs one króna less

So it is not agreeing with krónu as an adjective would. It is functioning more like English less in one dollar less.

That is a very natural place for a time expression in Icelandic.

• í dag = today

The sentence structure is perfectly normal:

• Kaffið kostar eina krónu minna í dag.

Icelandic word order is fairly flexible, so you could also move í dag to the front for emphasis:

• Í dag kostar kaffið eina krónu minna.

That would still be correct, but it slightly changes what is being highlighted.

Literally, it is:

• í = in
• dag = day

So word-for-word it looks like in day, but as a fixed expression it means today.

This is a very common Icelandic phrase.

Yes.

Króna is the Icelandic word for króna, the currency unit of Iceland.

So:

• ein króna = one króna
• tvær krónur = two krónur

In real life, one króna is a very small amount, but grammatically the sentence is completely normal.

A more word-for-word version would be:

The coffee costs one króna less today.

You could break it down like this:

• Kaffið = the coffee
• kostar = costs
• eina krónu = one króna
• minna = less
• í dag = today

So the Icelandic order is quite close to the English order in this sentence.

A rough pronunciation for English speakers is something like KAHF-fith.

A few helpful points:

• a is like a in father
• ff is a clear double f
• ð is like the th in this, though at the end it can sound weaker

So:

• kaffi ≈ KAHF-fi
• kaffið ≈ KAHF-fith

That last sound is often one learners need practice with.

Yes, that would also be a natural sentence.

It means roughly:

• The coffee is one króna cheaper today.

Compare the two patterns:

• Kaffið kostar eina krónu minna í dag. = The coffee costs one króna less today.

• Kaffið er eina krónu ódýrara í dag. = The coffee is one króna cheaper today.

Both are good Icelandic. The original sentence focuses on the cost being lower by one króna. The second uses the adjective ódýr = cheap, comparative ódýrara = cheaper.