Norms of age of acquisition and concreteness for 30,000 Dutch words

• We collected age-of-acquisition ratings for 30,000 Dutch words.
• We validated these ratings against existing, smaller databases.
• These ratings can be used in word processing experiments.

Word processing studies increasingly make use of regression analyses based on large numbers of stimuli (the so-called megastudy approach) rather than experimental designs based on small factorial designs. This requires the availability of word features for many words. Following similar studies in English, we present and validate ratings of age of acquisition and concreteness for 30,000 Dutch words. These include nearly all lemmas language researchers are likely to be interested in. The ratings are freely available for research purposes.