Superlative adjectives (-est)

To say that something is the tallest, newest, or fastest, add the suffix -est to the basic adjective. For example, høj (tall) becomes højest (tallest), and ny (new) becomes nyest (newest).

Is this building tallest?
Er denne bygning højest?
I think that the tower is tallest.
Jeg synes at tårnet er højest.
We believe that this tower is newest.
Vi tror at dette tårn er nyest.

When the superlative comes after the verb (as a predicative adjective in a general statement), it keeps this simple -est ending regardless of the noun's gender or whether it is singular or plural.

Are these cars fastest?
Er disse biler hurtigst?
Which bridge is strongest?
Hvilken bro er stærkest?
Which month is warmest?
Hvilken måned er varmest?

You will often see these superlative adjectives followed by a prepositional phrase to specify the context (like "in the class" or "in July").

The boy is smartest in the class.
Drengen er klogest i klassen.
The weather is often warmest in July.
Vejret er ofte varmest i juli.
The water in the river is coldest.
Vandet i floden er koldest.
The machine is fastest and strongest.
Maskinen er hurtigst og stærkest.