How to Install `nltk` in Python

v3.9.4 Data & Science Python >=3.10 Apache License, Version 2.0

Natural Language Toolkit

Install pip install nltk

What is nltk?

Natural Language Toolkit

The Natural Language Toolkit (NLTK) is a Python package for natural language processing. NLTK requires Python 3.10, 3.11, 3.12, 3.13, or 3.14.

Documentation → PyPI page → Author: NLTK Team

Quick Start

Minimal example to get started with nltk:

import nltk

print(nltk.__version__)

Installation

pip (standard)

pip install nltk

Virtual environment (recommended)

python -m venv venv
source venv/bin/activate   # Windows: venv\Scripts\activate
pip install nltk

pip3

pip3 install nltk

conda

conda install -c conda-forge nltk

Poetry

poetry add nltk

Dependencies

Installing nltk will also install these packages:

click joblib regex tqdm

Verify the Installation

After installing, confirm the package is available:

python -c "import nltk; print(nltk.__version__)"

If this prints a version number, installation succeeded. If you see a ModuleNotFoundError, see the errors section below.

Installation Errors

Common errors when installing nltk with pip.

ModuleNotFoundError: No module named 'nltk'

Cause: The package is not installed in the current Python environment.

Fix: Run pip install nltk. If using a virtual environment, ensure it is activated first.

ModuleNotFoundError: No module named 'nltk' (installed but still failing)

Cause: pip installed the package into a different Python than the one running your script.

Fix: Use python -m pip install nltk to install into the interpreter you are running.

ImportError: cannot import name 'X' from 'nltk'

Cause: The function or class does not exist in the installed version.

Fix: Check the version with pip show nltk and upgrade with pip install --upgrade nltk.

pip: command not found

Cause: pip is not in PATH or Python was not added to PATH during installation.

Fix: Try python -m pip install nltk. On macOS/Linux try pip3.

PermissionError: [Errno 13] Permission denied

Cause: No write access to the system Python package directory.

Fix: Use a virtual environment, or add --user: pip install --user nltk

SSL: CERTIFICATE_VERIFY_FAILED

Cause: pip cannot verify PyPI's SSL certificate — common behind corporate proxies.

Fix: Try: pip install --trusted-host pypi.org --trusted-host files.pythonhosted.org nltk

MemoryError when loading data

Cause: Dataset is too large to fit in RAM.

Fix: Read in chunks, filter columns on load, or consider Polars/Dask for out-of-core processing.

Recent Releases

Version	Released
`3.9.4` latest	2026-03-24
`3.9.3`	2026-02-24
`3.9.2`	2025-10-01
`3.9`	2024-08-18
`3.9.1`	2024-08-18

Full release history on PyPI →

Manage nltk

Upgrade to latest version

pip install --upgrade nltk

Install a specific version

pip install nltk==3.9.4

Uninstall

pip uninstall nltk

Check what is installed

pip show nltk

Last updated: 2026-04-11 • Data from PyPI

How to Install nltk in Python