What this means for learners
Dutch and GERMAN share 32 sounds — roughly 55% of GERMAN's inventory overlaps with Dutch. Shared sounds are ones a speaker already knows from their native language and will generally produce and perceive accurately without explicit training.
The 9 sounds found only in GERMAN represent the greatest pronunciation challenge for Dutch speakers. The adult brain tends to map unfamiliar sounds onto the closest native equivalent — a process that produces the characteristic "accent" of a second-language speaker. Learning to hear and produce these sounds as distinct requires focused ear training, not just repetition.
Conversely, Dutch has 26 sounds not used in GERMAN. Native GERMAN speakers learning Dutch will face the mirror-image challenge with these sounds.
Phoneme inventories from PHOIBLE. Data reflects one documented inventory per language; some variation exists across dialects and sources.