The key feature of the comparative form of adjectives is -abb/-ebb. We simply add -abb/-ebb to the dictionary form of the adjective to form the comparative verison.

• gyorsabb faster
• kisebb smaller
• melegebb hotter
• gazdagabb richer
• nagyobb larger (irregular)

On its own, -abb is only of limited use. To say, "I am smarter" is not very helpful without "than you".

We form this by adding , mint ....

• Én nagyobb vagyok, mint te I am larger than you.
• Te gyorsabb vagy, mint én You are faster than I*.
• Ő kisebb, mint én He is smaller than I*.
• Ők gazdagabbak, mint én They are richer than I*.
• Ez a toll jobb, mint az enyém This pen is better than mine.
• Ez a toll nem jobb, mint az enyém This pen is not better than mine.
• Ági lassabban vezet, mint Daniel. Ági drives more slowly than Daniel.**

Note the comma. This literally translates as I am smarter, than you.
You are taller, than I.

*I Note how it's correct to say, than I, not than me. See my page on English pronouns

** Note that we say lassabban, more slowly ; we do not say slower. See the section on adverbs.

There is a second way of saying than. This does not use mint, nor the comma, rather the target of the comparison is put into the -nál/-nél (adessive) form.

• Én nagyobb vagyok nálad. I am larger than you.
• Te gyorsabb vagy nála. You are faster than he.
• Ő kisebb nálam. He is smaller than I.
• Ők gazdagabbak nálunk. They are richer than we.
• Ez a toll jobb az enyémnél. This pen is better than mine.
• Ez a toll nem jobb az övénél. This pen is not better than his.
• Ági lassabban vezet Danielnél. Ági drives more slowly than Daniel.

Note that we can only use this form in comparative statements, in which this form of the pronoun replaces mint in its than form. It cannot be used in equality statements because it cannot replace mint in its as form.
Thanks to Sárándi István for his explanation of this subtle point.

Just like with absolute (dictionaty) forms of adjectives , we must put the comparative forms into the plural when they are in predicative form.

• Ez a lány magasabb, mint az a fiú? Is this girl taller than that boy?
• Ezek a lányok magasabbak, mint azok a fiúk? Are these girls taller than those boys?

Here is a great example, from Whitney, which compares the London and Budapest bridges. He uses both the mint and the -nál/-nél forms to show their equivilence. Note well how when we compare plural objects, we also but the adjective into the plural.

• London nagyobb Budapestnél?
  Is London larger than Budapest?
• Igen, sokkal nagyobb, és sokkal több híd van Londonban, mint Budapesten.
  Yes, much larger, and there are many more bridges in London than in Budapest.
• Hosszabbak a londoni hidak, mint a budapesti hidak?
  Are the London bridges longer than the Budapest bridges?
• Nem, a budapesti hidak hosszabbak a londoni hidaknál
  No, the Budapest bridges are longer than the London bridges.
• Minél szebb a lány, annál büszkébb a fiú.
  The more beautiful the girl, the prouder the boy.
• Budapesten több híd van, az egyik szebb, mint a másik.
  The are several bridges in Budapest, each more beautiful than the next.
• Ez szebb a többinél.
  This is more beautiful than the others.
• Minél nagyobb a forgalom, annál több hídra van szükség.
  The more traffic, the more bridges are needed.