# Installation

Users can install the current version of **ipywidgets** with
[pip](https://pip.pypa.io/en/stable/) or
[conda](https://conda.readthedocs.io/en/latest/).

In most cases, installing the Python `ipywidgets` package will also automatically configure classic Jupyter Notebook and JupyterLab 3.x to display ipywidgets. With pip, do:

```bash
pip install ipywidgets
```

or with conda, do:

```bash
conda install -c conda-forge ipywidgets
```

## Installing in JupyterLab 3.x

Most of the time, installing `ipywidgets` automatically configures JupyterLab 3.x to use widgets. The `ipywidgets` package does this by depending on the `jupyterlab_widgets` package, which configures JupyterLab 3 to display and use widgets.

If JupyterLab and the IPython kernel are installed in different
environments (for example, separate environments are providing different
Python kernels), then the installation requires two steps:

1. Install the `jupyterlab_widgets` package in the environment containing JupyterLab.
2. Install `ipywidgets` in each kernel's environment that will use ipywidgets.

For example, if using conda environments, with JupyterLab installed on the
`base` environment and the kernel installed in an environment called `pyenv`,
the commands are:

```bash
conda install -n base -c conda-forge jupyterlab_widgets
conda install -n pyenv -c conda-forge ipywidgets
```

## Installing in classic Jupyter Notebook

Most of the time, installing `ipywidgets` automatically configures Jupyter Notebook to use widgets. The `ipywidgets` package does this by depending on the `widgetsnbextension` package, which configures the classic Jupyter Notebook to display and use widgets.

If your Jupyter Notebook and the IPython kernel are installed in different
environments (for example, separate environments are providing different
Python kernels), then the installation requires two steps:

1. Install the `widgetsnbextension` package in the environment
   containing the Jupyter Notebook server.
2. Install `ipywidgets` in each kernel's environment that will use ipywidgets.

For example, if using conda environments, with Jupyter Notebook installed on the
`base` environment and the kernel installed in an environment called `pyenv`,
the commands are:

```bash
conda install -n base -c conda-forge widgetsnbextension
conda install -n pyenv -c conda-forge ipywidgets
```

## Installing into JupyterLab 1 or 2

To install the JupyterLab extension into JupyterLab 1 or 2, you also need to run the command below in
a terminal which requires that you have [nodejs](https://nodejs.org/en/)
installed.

For example, if using conda environments, you can install nodejs with:

```bash
conda install -c conda-forge nodejs
```

Then you can install the labextension:

```bash
jupyter labextension install @jupyter-widgets/jupyterlab-manager
```

This command defaults to installing the latest version of the **ipywidgets**
JupyterLab extension. Depending on the version of JupyterLab you have installed, you
may need to install [an older version](https://github.com/jupyter-widgets/ipywidgets/tree/main/packages/jupyterlab-manager#version-compatibility).

If you install this extension while JupyterLab is running, you will need to
refresh the page or restart JupyterLab before the changes take effect.

**Note:** A clean reinstall of the JupyterLab extension can be done by first
running the `jupyter lab clean` command which will remove the staging and
static directories from the lab directory. The location of the lab directory
can be queried by executing the command `jupyter lab path` in your terminal.

## Installing into classic Jupyter Notebook 5.2 or earlier

If you have an old version of Jupyter Notebook installed (version 5.2 or
earlier), you may need to manually enable the ipywidgets notebook extension
with:

```bash
jupyter nbextension enable --py widgetsnbextension
```

When using [virtualenv](https://virtualenv.pypa.io/en/stable/) and working in
an activated virtual environment, the `--sys-prefix` option may be required
to enable the extension and keep the environment isolated (i.e.
`jupyter nbextension enable --py widgetsnbextension --sys-prefix`).

## Frequently Asked Questions

The issues in the [Reference milestone](https://github.com/jupyter-widgets/ipywidgets/issues?q=is%3Aopen+is%3Aissue+milestone%3AReference) on GitHub include many questions, discussions,
and answers about ipywidgets.

**Question**: When I display a widget or interact, I just see some text, such as `IntSlider(value=0)` or `interactive(children=(IntSlider(value=0, description='x', max=1), Output()), _dom_classes=('widget-interact',))`. What is wrong?

**Answer**: A text representation of the widget is printed if the widget control
is not available. It may mean the widget JavaScript is still loading. If the
message persists in the Jupyter Notebook or JupyterLab, it likely means that the
widgets JavaScript library is either not installed or not enabled. See the
installation instructions above for setup instructions.

If you see this message in another frontend (for example, a static rendering on
GitHub or <a href="https://nbviewer.jupyter.org/">NBViewer</a>), it may mean
that your frontend doesn't currently support widgets.