This study aims at defining and analyzing voicing profile of Polish sonorant [r] showing the variability of its realizations depending on segmental and prosodic position. Voicing profile is defined as the frame-by-frame voicing status of a speech sound in continuous speech. Word-final devoicing of sonorants is shortly reviewed and analyzed in terms of the conducted corpus-based investigation. We used automatic tools to extract consonants features, F0 values and obtain voicing profile. The results show that liquid [r] devoice word and syllable finally, particularly with left voiceless stop context.