-er Forms
Comparing two things in German usually just means adding -er to the adjective, plus an umlaut on the stem vowel for many short words.
Add -er, then say what it's being compared to
The comparative form is the same regardless of gender or case: just the adjective plus -er, with als ("than") introducing the second thing being compared.
Er ist schnell.
Er ist schneller als sie.
schnell becomes schneller, and als introduces exactly who or what he's faster than.
Regular -er, and When to Add an Umlaut
Most adjectives just add -er. Many common one-syllable adjectives with a, o, or u in the stem also pick up an umlaut in the comparative.
| Base | Comparative |
|---|---|
| schnell | schneller |
| alt | älter |
| jung | jünger |
| groß | größer |
| kalt | kälter |
| lang | länger |
There's no shortcut for which words take the umlaut: it just has to be learned per adjective.
The Irregulars Worth Memorizing
A handful of extremely common adjectives don't follow the -er pattern at all.
See It In a Sentence
The comparative form is highlighted below, wherever it lands in the sentence.
Diese Stadt ist größer als meine Heimatstadt.
This city is bigger than my hometown.
Otto trinkt lieber Tee, aber seine Katze mag Milch lieber.
Otto prefers tea, but his cat prefers milk even more.
Heute ist es kälter als gestern.
It's colder today than yesterday.
A Common Mix-Up
English speakers sometimes reach for a separate word like mehr ("more") in front of the adjective, the way English uses "more interesting." German almost never does this for simple adjectives: interessanter, not mehr interessant. Save mehr for comparing amounts of a noun, not the adjective itself.