Dutch comparative and superlative (-er / -st)

To say that one thing has more of a quality than another, Dutch adds -er to the adjective (the comparative): klein → kleiner (small → smaller). To mark the top of the scale, it adds -st (the superlative): klein → kleinst (smallest). The pattern groot, groter, grootst (big, bigger, biggest) is the model for almost every adjective.

Add -er to the plain adjective: snel → sneller (fast → faster), mooi → mooier (beautiful → more beautiful). One group changes the ending: adjectives that already end in -r add -der instead of -er, to keep them pronounceable.

1. Most adjectives: add -er. goedkoop → goedkoper (cheap → cheaper), warm → warmer (warm → warmer).
2. Adjectives ending in -r: add -der. duur → duurder (expensive → more expensive), lekker → lekkerder (tasty → tastier), zwaar → zwaarder (heavy → heavier).
3. The comparative can take the adjective -e ending before a noun, exactly like a plain adjective: een groter huis (a bigger house), de snellere trein (the faster train). See the adjective -e ending.

Add -st to the plain adjective: snel → snelst, mooi → mooist. Before a noun the superlative takes -ste and usually stands with de or het: de snelste trein (the fastest train), het mooiste huis (the most beautiful house), de grootste steden (the biggest cities).

When the superlative is not in front of a noun but describes the subject ("is the most ..."), Dutch uses het + -st: In de winter zijn de dagen het kortst. (In winter the days are the shortest.) Deze route is het snelst. (This route is the fastest.)

The endings follow the ordinary Dutch spelling rules, so the stem can change when you add -er.

• A long vowel written double loses one letter before -er, because the syllable opens up: groot → groter, goedkoop → goedkoper. The superlative -st keeps the syllable closed, so the vowel stays double: grootst. This is the open/closed-syllable rule.
• A short vowel doubles the following consonant before -er, to stay short: dik → dikker → dikst (thick), dun → dunner → dunst (thin).
• A final -f or -s that comes from an underlying v or z turns back into v/z before -er: lief → liever would clash with another word, so take vies → viezer (dirty → dirtier) and braaf → braver (well-behaved → better-behaved). This is why v becomes f and z becomes s.

Some adjectives do not take -er / -st comfortably. For these, put meer (more) or meest (most) in front of the plain adjective, the way English uses "more" and "most".

• Adjectives ending in -isch keep a regular comparative in -er — typisch → typischer (typical → more typical), logisch → logischer (logical → more logical) — but avoid -st in the superlative and take meest instead: het meest typisch (the most typical), het meest praktisch (the most practical).
• Adjectives that already end in -st: meest juist (most correct), de meest gepaste (the most appropriate).
• Long or hard-to-pronounce adjectives, where -er/-st would sound clumsy: meer gemotiveerd (more motivated), het meest ontspannen (the most relaxed).

A handful of everyday adjectives do not follow any of these patterns at all: goed becomes beter and best, not goeder. Those are covered on irregular comparison. For the word that follows a comparative — groter dan or groter als — see dan or als in comparisons.