German adjective endings

The topic teachers most often name as the hardest, and the table everyone screenshots and then loses. Nobody derives this live in conversation, which is exactly why it belongs in print.

The one rule underneath all of it

Something in the noun phrase has to show the case and gender. If the word before the adjective already shows it, the adjective relaxes into -e or -en. If nothing shows it, the adjective does the work and takes the ending the definite article would have had.

That sentence explains all three tables. The rest is it, spelled out.

Weak — after der, die, das, dieser, jeder, welcher, alle

	masculine	feminine	neuter	plural
Nom	der gute Mann	die gute Frau	das gute Kind	die guten Kinder
Akk	den guten Mann	die gute Frau	das gute Kind	die guten Kinder
Dat	dem guten Mann	der guten Frau	dem guten Kind	den guten Kindern
Gen	des guten Mannes	der guten Frau	des guten Kindes	der guten Kinder

Shortcut: -e in the top-left corner (five slots), -en everywhere else.

Mixed — after ein, kein, mein, dein, sein, ihr, unser, euer

	masculine	feminine	neuter	plural
Nom	ein guter Mann	eine gute Frau	ein gutes Kind	keine guten Kinder
Akk	einen guten Mann	eine gute Frau	ein gutes Kind	keine guten Kinder
Dat	einem guten Mann	einer guten Frau	einem guten Kind	keinen guten Kindern
Gen	eines guten Mannes	einer guten Frau	eines guten Kindes	keiner guten Kinder

Mixed differs from weak in exactly three boxes — nominative masculine (-er), nominative neuter (-es), accusative neuter (-es). Those are precisely where ein has no ending of its own, so the adjective shows the gender instead. Learn the weak table, then patch three squares.

Strong — no determiner at all

	masculine	feminine	neuter	plural
Nom	guter Wein	gute Milch	gutes Bier	gute Weine
Akk	guten Wein	gute Milch	gutes Bier	gute Weine
Dat	gutem Wein	guter Milch	gutem Bier	guten Weinen
Gen	guten Weines	guter Milch	guten Bieres	guter Weine

These are the der/die/das endings transplanted onto the adjective (der → -er, das → -es, dem → -em). Only genitive masculine and neuter break the pattern, taking -en rather than -es.

Strong endings appear more than beginners expect: after numbers (drei kleine Kinder), in plurals with no article (deutsche Autos), and after viele, wenige, einige, mehrere, andere.

But after alle, beide, sämtliche the adjective is weak: alle guten Menschen.

The mistake to name explicitly

Learners mix up noun declension with adjective declension and end up declining both or neither. The noun mostly does not change (cases and articles: dative plural -n, genitive -s). The adjective changes constantly. When in doubt, the adjective is the one doing the work.

Two extras

• After etwas, nichts, viel, wenig the adjective is neuter and capitalised: etwas Neues, nichts Gutes.
• hoch drops its c: ein hoher Berg. teuer and dunkel drop the e: ein teures Auto, ein dunkles Zimmer.