CLAWS

Part of speech tagging for English texts.

 http://ucrel-api.lancaster.ac.uk/claws/free.html

Free tagging service for up to 100,000 running words of text.

Part-of-speech (POS) tagging, also called grammatical tagging, is the commonest form of corpus annotation, and was the first form of annotation to be developed by UCREL at Lancaster. The POS tagging software for English text, CLAWS (the Constituent Likelihood Automatic Word-tagging System), has been continuously developed since the early 1980s. The latest version of the tagger, CLAWS4, was used to POS tag c.100 million words of the British National Corpus (BNC).