To say one thing is bigger, smaller, or more interesting than another, Dutch adds -er to the adjective — almost exactly the way English adds -er to short words. Groot becomes groter, klein becomes kleiner, mooi becomes mooier. The good news for English speakers is that Dutch uses the -er ending for all adjectives, long or short, so there is no "more interesting"-style two-word form to worry about (that's covered under the superlative's meest). The two things to watch are a small spelling twist with adjectives ending in -r, and the all-important choice of dan for "than."
The basic rule: add -er
Take the adjective and add -er. The open/closed-syllable spelling rules apply exactly as they do everywhere else.
| Adjective | Comparative | Spelling note |
|---|---|---|
| klein | kleiner | nothing changes |
| mooi | mooier | nothing changes |
| groot | groter | long oo → single o (open syllable: gro-ter) |
| dik | dikker | short i → double the k (dik-ker) |
| interessant | interessanter | one word, no meer |
| nieuw | nieuwer | nothing changes |
The two spelling cases are the same ones you already know from plurals and conjugations. Groot has a long oo in a closed syllable; adding -er opens the syllable (gro-ter), so the long vowel drops to a single o: groter. Dik has a short i; to keep it short before the vowel-ending, the k doubles: dikker. If those feel familiar, it's because the comparative -er triggers the very same machinery as the plural -en.
Mijn nieuwe telefoon is veel sneller dan de oude.
My new phone is much faster than the old one.
Dit boek is interessanter dan ik dacht.
This book is more interesting than I expected. — one word: interessanter.
Het wordt elke dag een beetje kouder.
It gets a little colder every day.
Adjectives in -r take -der, not -rer
Here is the one genuinely Dutch-specific twist. If an adjective already ends in -r, you do not add a plain -er — you add -der instead. So duur ("expensive") becomes duurder, not duurrer.
| Adjective | Comparative |
|---|---|
| duur (expensive) | duurder |
| ver (far) | verder |
| lekker (tasty) | lekkerder |
| zwaar (heavy) | zwaarder |
| helder (clear) | helderder |
This is not an arbitrary exception list you have to memorise — it's a single pronounceability rule. Dutch r is already a full, often rolled or guttural sound; stacking -rer on top of it (duurrer) would force two r-sounds together that the language won't tolerate. Inserting a -d- breaks them up: duur-der. Once you know the reason, you can predict it for any -r adjective you meet, including ones already ending in -er like lekker → lekkerder.
Een huis in het centrum is veel duurder dan hier.
A house in the city centre is much more expensive than here.
Het station is verder dan je denkt — neem de fiets.
The station is farther than you think — take the bike.
Deze soep is nog lekkerder met wat verse kruiden.
This soup is even tastier with some fresh herbs.
The comparative still inflects attributively
When the comparative sits in front of a noun, it behaves like any other attributive adjective and takes the usual -e ending. So groter becomes grotere before a noun, duurder becomes duurdere.
We zoeken een grotere auto nu we kinderen hebben.
We're looking for a bigger car now that we have children.
Hij wil een duurdere fiets, maar dat past niet in het budget.
He wants a more expensive bike, but that doesn't fit the budget.
Er staat een interessantere baan op de website.
There's a more interesting job on the website.
So the comparative stacks two endings: first -er (or -der) to make the comparative, then -e for the attributive position. groot → groter → grotere.
"Than" is dan, not als
After a comparative, "than" is dan. This matters because spoken Dutch is full of people using als here (groter als ik), and while you will hear it constantly, it is stigmatised and considered incorrect in careful and written Dutch. Stick with dan after every comparative.
Hij is groter dan zijn broer.
He's taller than his brother. — dan, never 'als'.
Ik verdien minder dan vorig jaar.
I earn less than last year.
Niemand kookt beter dan mijn oma.
Nobody cooks better than my grandmother.
How this differs from English
English splits comparatives into two systems: -er for short words (bigger, faster) and more for longer ones (more interesting, more expensive). Dutch uses -er for everything, so interessanter and duurder are single words where English needs two. That's actually simpler — but English speakers often reach for a meer + adjective construction by analogy with "more," which is wrong for ordinary comparatives. The other trap is the reverse of an English instinct: English never inserts a consonant, so the -der on -r adjectives (duurder) feels alien and gets dropped.
Common Mistakes
❌ Hij is groter als zijn broer.
Wrong (stigmatised) — use 'dan' after a comparative.
✅ Hij is groter dan zijn broer.
He's taller than his brother.
❌ een meer interessant boek
Wrong — Dutch uses the -er ending, not 'meer', for ordinary comparatives.
✅ een interessanter boek
A more interesting book.
❌ Dit is duurer dan dat.
Wrong — an -r adjective takes -der, not plain -er.
✅ Dit is duurder dan dat.
This is more expensive than that.
❌ Het is grooter dan ik dacht.
Wrong spelling — adding -er opens the syllable, so the oo drops to a single o.
✅ Het is groter dan ik dacht.
It's bigger than I expected.
❌ We willen een groter auto.
Wrong — the comparative still inflects attributively.
✅ We willen een grotere auto.
We want a bigger car.
Key Takeaways
- Form the comparative by adding -er to the adjective — for all adjectives, long or short (interessanter, not meer interessant).
- The open/closed-syllable spelling applies: groot → groter, dik → dikker.
- Adjectives ending in -r take -der instead (duur → duurder, ver → verder) because -rer is unpronounceable — a phonological rule, not an exception list.
- The comparative still takes attributive -e: groter → grotere auto.
- "Than" is dan, never als, after a comparative — als is widespread in speech but stigmatised.
Now practice Dutch
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Start learning Dutch→Related Topics
- The Superlative (-st)A2 — Forming the Dutch superlative with -st, its attributive het/de …-ste form, the puzzling double-het predicate (het …-st), and when to fall back on meest.
- Irregular Comparison: Goed, Veel, GraagB1 — The suppletive comparatives and superlatives — goed→beter→best, veel→meer→meest, weinig→minder→minst — plus graag→liever→liefst, Dutch's everyday way to say 'rather' and 'prefer'.
- Als vs Dan in ComparisonsA2 — After a comparative, Dutch uses dan (groter dan ik, meer dan tien); for equality, it uses zo + adjective + als (net zo groot als). English speakers don't have this problem from their own language, but they hear native speakers say the substandard 'groter als' everywhere. This page gives the clean written rule, head-to-head pairs, and the reason 'groter als' is a shibboleth.
- Open and Closed Syllables: The Doubling RuleA1 — The keystone of Dutch spelling — how open vs closed syllables control vowel-letter and consonant-letter doubling, the rule behind nearly every plural, conjugation, and diminutive.
- The -e Rule and Its One Big ExceptionA1 — Before a noun, a Dutch adjective takes -e — always — with exactly one exception: a singular het-word introduced by een or no article keeps the adjective bare (een mooi huis). Master that one cell and the whole rule is yours.