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NLTK

open source / Overall score: 4.2(strong)

The Natural Language Toolkit, a suite of Python modules for tokenization, stemming, tagging, chunking, parsing, classification, language modeling and semantic reasoning, with interfaces to more than 50 corpora and lexical resources such as WordNet. It supports research and development in natural language processing, and is a community project led by Steven Bird since 2001.

Openness

5 high confidence

5.0

license: Apache-2.0(OSI
source: public(github.com/nltk/nltk)
core features withheld: no — community-driven

The code is Apache-2.0 and builds whole from the public repository, which has no enterprise, commercial or pro directory. Its documentation is under a non-commercial Creative Commons license and each corpus carries its own terms, but those cover the manuals and the data, not the library.

https://cdn.jsdelivr.net/gh/nltk/nltk@develop/LICENSE.txt recorded 2026-09-26
LICENSE.txt is the Apache License, Version 2.0 text with the unfilled appendix template.
https://cdn.jsdelivr.net/gh/nltk/nltk@develop/README.md recorded 2026-09-26
README: "NLTK source code is distributed under the Apache 2.0 License." / "NLTK documentation is distributed under the Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 United States license." / "Copyright (C) 2001-2026 NLTK Project".
https://data.jsdelivr.com/v1/packages/gh/nltk/nltk@develop?structure=flat recorded 2026-09-26
Flat file listing of develop, 498 paths, with no ee, enterprise, commercial or pro directory.
https://www.nltk.org/ recorded 2026-09-26
Homepage: "Best of all, NLTK is a free, open source, community-driven project."

Adoption

5 high confidence

5.0

Measured on monthly PyPI downloads of the nltk package.

https://pypistats.org/api/packages/nltk/recent recorded 2026-09-26
last_month 42,218,083 downloads of nltk

Capability

3 medium confidence

3.0

NLTK covers the classical NLP pipeline end to end with many learners - taggers, parsers, classifiers - and the corpora to train them on. It is a toolkit to build with, and leaves the choice among its methods to the user.

https://www.nltk.org/ recorded 2026-09-26
Homepage: "easy-to-use interfaces to over 50 corpora and lexical resources such as WordNet, along with a suite of text processing libraries for classification, tokenization, stemming, tagging, parsing, and semantic reasoning".
https://www.nltk.org/py-modindex.html recorded 2026-09-26
Module index: ccg, chat, chunk, classify, cluster, collocations, corpus, grammar, inference, lm, metrics, parse, probability, sem, sentiment, stem, tag, tbl, tokenize, translate, tree, wsd.

Verified 2026-09-26