Swedish adjectives change shape to agree with the noun they describe. This page covers one slice of that system: the neuter -t form, the ending an adjective takes when it modifies an ett-word (a neuter noun). English adjectives never change — a red house, a red car, red houses all keep red untouched. Swedish makes the adjective match, and the neuter match is a single added -t. Most of the difficulty is not the rule itself but a handful of predictable spelling shifts that the -t triggers, plus a small group of adjectives that refuse to take it at all. (The plural and definite -a ending is a separate topic — see The Indefinite Form.)
The basic rule: add -t for ett-words
A Swedish adjective has a base form (the one in the dictionary), which is used with en-words in the singular indefinite. For ett-words you add -t. This holds in two positions: directly in front of the noun (ett rött hus) and after the verb vara "to be" (huset är rött).
Vi har ett rött hus och en röd bil.
We have a red house and a red car. ett hus → rött (neuter, +t); en bil → röd (base form, no ending).
Huset är rött men taket är vitt.
The house is red but the roof is white. After 'är' the adjective still agrees with its noun: huset → rött, taket → vitt.
So the choice is driven entirely by the noun's gender. If you know the noun is ett barn (a child), you know the adjective gets -t: ett litet barn är trött "a small child is tired." The whole reason gender matters here is that it dictates this ending — which is exactly why learning a noun's gender alongside the noun pays off immediately.
The spelling shifts: d/t → tt
Here is the part competitors present as a list of exceptions to memorize. It is not — it is regular phonology. Swedish does not allow a single consonant after a short stressed vowel at the end of a syllable in this position, so when you add -t to a stem already ending in -d or -t, the result is written -tt, not -dt or -tt + t.
- Stem in -d: the -d turns into -t and joins the suffix: röd → rött, god → gott, glad → glatt, bred → brett.
- Stem in -t (short vowel): the consonant doubles: vit → vitt, lätt stays lätt (see below), söt → sött.
Det var ett gott kaffe och ett sött bröd.
That was a good coffee and a sweet bread. god → gott (d→tt), söt → sött (t→tt after a long vowel shortened).
Barnet blev glatt när det fick ett brett leende tillbaka.
The child became happy when it got a broad smile back. glad → glatt, bred → brett — both -d stems write -tt in the neuter.
The logic is worth holding onto: you are not memorizing that röd "becomes" rött as a quirk. You are applying one sound rule — a final -d or -t before the neuter -t is written -tt — that covers röd, god, glad, bred, vit, söt, vid, hård and every other stem of this shape. One rule, not a list.
Brödet är hårt och golvet är kallt.
The bread is hard and the floor is cold. bröd → hårt (here the long vowel keeps a single t); golv → kallt (regular +t on an -ll stem). Both are ett-words.
Stems already ending in -t: no extra t
If an adjective already ends in -tt or in a long-vowel + -t, you do not stack another -t on top. The most common everyday case is lätt "easy/light," which already has -tt and stays put:
Det är ett lätt jobb och ett rätt svar.
It's an easy job and a correct answer. lätt and rätt already end in -tt — no extra ending in the neuter.
This is why you must look at the shape of the stem, not just reach for "+t" mechanically. Lätt hus would never be lättt; the -tt is already there.
Past participles in -ad → -at
This is the unifying insight. Past participles used as adjectives (målad "painted," stängd "closed," köpt "bought") follow the same neuter rule. The very common -ad type becomes -at in the neuter:
Vi har en målad vägg hemma och ett målat staket ute.
We have a painted wall at home and a painted fence outside. målad → målat: the -ad participle drops to -at for the ett-word, exactly the neuter rule.
Köket är nymålat och fönstret är stängt.
The kitchen is freshly painted and the window is closed. nymålad → nymålat, stängd → stängt — participles agree like ordinary adjectives.
Once you see that målad → målat is the same mechanism as röd → rött, you stop treating participle agreement as a second system. It is the same neuter -t, applied to a word that happens to be built from a verb. (More on participle forms on The Past Participle.)
Invariable adjectives: never take -t
A real group of adjectives simply never changes — no neuter -t, no plural -a, nothing. You have to recognize them, because adding -t to one is a clear error. The big everyday members:
- bra (good), kul (fun), slut (finished/over), äkta (genuine), gratis (free of charge)
- Most adjectives ending in unstressed -e or -a: öde (deserted), ringa (slight), stilla (calm), and color loans like rosa (pink), lila (purple), beige.
Det är ett bra hus och ett kul jobb.
It's a good house and a fun job. bra and kul are invariable — NOT 'ett brat hus', never *bra→brat.
Festen är slut och vinet är gratis.
The party is over and the wine is free. slut and gratis don't agree with anything.
Vi målade ett rosa rum med öde väggar.
We painted a pink room with bare walls. rosa stays rosa even before an ett-word — not *rosat.
There is no deep reason bra resists agreement while god takes it — it is simply a closed list you memorize. The honest advice: learn bra, kul, slut, gratis, äkta and "adjectives ending in -a/-e" as the invariable set, and treat everything else as agreeing normally.
Stems in å, ä, ö
Adjectives whose stem ends in a stressed vowel just add -tt (the doubled spelling marks the preceding short vowel in writing), and the vowel itself is unchanged — keep the diacritic:
Det var ett blått hav under en grå himmel, och vattnet var nytt och kallt.
It was a blue sea under a grey sky, and the water was new and cold. blå → blått, grå → grått (here describing himmel, an en-word, so grå stays base); ny → nytt.
Ett nytt år och ett blått ljus i fönstret.
A new year and a blue light in the window. ny → nytt, blå → blått — vowel stems double the t.
Note ny → nytt, blå → blått, grå → grått: the å survives intact, and you simply hear and write a doubled t. Never "fix" blått by dropping the å.
Common Mistakes
❌ ett röd hus
Incorrect — an ett-word needs the neuter -t on the adjective.
✅ ett rött hus
a red house — röd → rött (the -d writes as -tt).
❌ huset är god
Incorrect — agreement holds after 'är' too; the ett-word demands the -t form.
✅ huset är gott
the house is good — god → gott.
❌ ett brat hus / ett kult jobb
Incorrect — bra and kul are invariable and never take -t.
✅ ett bra hus / ett kul jobb
a good house / a fun job.
❌ ett lättt jobb
Incorrect — lätt already ends in -tt; you don't add another t.
✅ ett lätt jobb
an easy job.
❌ ett målad staket
Incorrect — the participle agrees like any adjective: -ad → -at in the neuter.
✅ ett målat staket
a painted fence.
Key Takeaways
- For an ett-word, an adjective takes -t: ett rött hus, and also after vara/bli — huset är rött.
- A stem ending in -d or short-vowel -t writes the result as -tt: röd → rött, god → gott, glad → glatt, vit → vitt. This is one regular sound rule, not a list of exceptions.
- Stems already ending in -tt take nothing extra: ett lätt jobb, ett rätt svar.
- Past participles in -ad follow the same rule: målad → målat (ett målat hus).
- Vowel stems double the t and keep the diacritic: ny → nytt, blå → blått, grå → grått.
- A closed set is invariable — bra, kul, slut, äkta, gratis, the color loans rosa/lila/beige, and most -a/-e adjectives: never add -t (ett bra hus, not ett brat hus).
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Start learning Swedish→Related Topics
- The Indefinite (Strong) DeclensionA1 — The three-form adjective declension that agrees with an indefinite noun: base form with en-words (en stor bil), +t with ett-words (ett stort hus), and +a in the plural and predicatively (stora bilar, bilarna är stora).
- Grammatical Gender: en and ettA1 — Swedish's two-gender system — common-gender en-words (~75%) and neuter ett-words (~25%) — and the honest truth that gender is mostly arbitrary and learned per word. Plus the genuine tendencies that cut the guesswork (unstressed -a is almost always en), and why gender matters: it drives the article, the definite ending, and the -t neuter form on adjectives.
- Irregular and Invariable AdjectivesB1 — The adjectives that break the regular -t / -a pattern: invariables that never change (bra, kul, rosa), stems that drop their unstressed vowel (gammal → gamla, vacker → vackra, öppen → öppna), and the wildly suppletive liten (liten / litet / lilla / små).
- The Past Participle (Agreeing Form)B1 — The past participle (perfektparticip) is the form that AGREES with its noun — målad/målat/målade, skriven/skrivet/skrivna — and is used as an adjective and in the bli/vara-passive. It is a different word from the supine (skrivit), even when they come from the same verb, and strong verbs often show a different vowel in the two: supine skrivit but participle skriven.