The methods to measure vocabulary size vary across disciplines. This heterogeneity hinders direct comparisons between studies and slows down the understanding of research findings. A quick, free and efficient test of English language proficiency, LexTALE, was recently developed to remedy this problem. LexTALE has been validated and shown to be an effective tool for distinguishing between different levels of proficiency in English. The test has also been made available in Dutch, German, and French. The present study discusses the development of a Spanish version of the test: Lextale-Esp. The test discriminated well at the high and the low end of Spanish proficiency and returned a big difference between the vocabulary size of Spanish native and non-native speakers.