Miðinn er ódýrari á netinu.

Because miðinn means the ticket, while miði means a ticket or just ticket.

In Icelandic, the definite article is usually attached to the end of the noun rather than written as a separate word.

• miði = ticket
• miðinn = the ticket

So the sentence is talking about a specific ticket, or tickets in a general definite sense, not just any ticket.

Miðinn is in the nominative singular.

That is because it is the subject of the sentence, and subjects are normally in the nominative in Icelandic.

You can break it down like this:

• miði = nominative singular indefinite
• -inn = the definite article attached to the noun

So miðinn is the ticket in nominative singular.

Er is the present tense of the verb að vera, meaning to be.

So:

• ég er = I am
• þú ert = you are
• hann/hún/það er = he/she/it is

In this sentence, miðinn is a third-person singular subject, so er is the correct form:

• Miðinn er ... = The ticket is ...

Ódýrari is the comparative form of ódýr, which means cheap.

So:

• ódýr = cheap
• ódýrari = cheaper

Icelandic often forms comparatives by adding -ari or -ri to the adjective, depending on the word.

Here the idea is the same as English cheap → cheaper.

Because Icelandic, like English, does not always need to say the second part of the comparison if it is clear from context.

English does the same thing:

• The ticket is cheaper online.

This implies something like:

• cheaper than at the counter
• cheaper than in person
• cheaper than elsewhere

If you wanted to say the full comparison in Icelandic, you could add en = than:

• Miðinn er ódýrari á netinu en í miðasölunni.
• The ticket is cheaper online than at the ticket office.

Á netinu means on the internet or simply online.

It consists of:

• á = on
• netinu = the internet / the net, in the dative definite form

This is a very common Icelandic expression for online.

So even though it literally looks like on the net, it is just the normal way to say online in many contexts.

Because the preposition á can take different cases depending on meaning.

A very useful rule is:

• á + dative for location / being somewhere
• á + accusative for motion toward / onto something

Here the meaning is static location, in the sense of on the internet / online, so Icelandic uses the dative.

That is why you get:

• netið = the internet, nominative/accusative definite
• netinu = the internet, dative definite

So á netinu literally uses á + dative.

Yes. In this sentence, ódýrari is describing miðinn, so it agrees with it.

Since miðinn is:

• masculine
• singular
• nominative

the adjective appears in the matching comparative form: ódýrari.

This is one reason Icelandic adjectives can feel more complicated than English adjectives: they often have to match the noun they describe.

Because that is a very normal word order in Icelandic.

The structure here is:

• Miðinn = subject
• er = verb
• ódýrari = complement
• á netinu = adverbial phrase telling where/in what context

So the sentence flows naturally as:

• The ticket is cheaper online.

You can sometimes move parts around for emphasis, but this version is the most neutral and natural.

For example, you might also see:

• Á netinu er miðinn ódýrari.

That puts more emphasis on online.

Yes. In many cases, both are good English translations.

• á netinu = online
• á netinu = on the internet

Which English version sounds best depends on context.

For this sentence, online is usually the most natural translation in English, because that is how we normally talk about buying tickets.

You would usually remove the definite article from the noun:

• Miði er ódýrari á netinu.

However, Icelandic often prefers a more natural phrasing depending on context, and bare singular nouns do not always behave exactly like English a ticket. In real usage, people might also choose a plural or a slightly different structure depending on what they mean.

But grammatically, the key difference is:

• miði = a ticket / ticket
• miðinn = the ticket

A rough guide is:

• miðinn ≈ MIH-thin or MIH-dhin

A few notes:

• í is a long ee sound
• ð is like the th in this
• the nn at the end is pronounced clearly

So it is not like English mid-in. The ð sound is important.

A very rough English-style approximation would be MEE-thin, though no approximation is perfect.