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Display a checkbox widget.

Function signature[source]

st.checkbox(label, value=False, key=None, help=None, on_change=None, args=None, kwargs=None, *, disabled=False, label_visibility="visible", width="content", bind=None)

Parameters

label (str)

A short label explaining to the user what this checkbox is for. The label can optionally contain GitHub-flavored Markdown of the following types: Bold, Italics, Strikethroughs, Inline Code, Links, and Images. Images display like icons, with a max height equal to the font height.

Unsupported Markdown elements are unwrapped so only their children (text contents) render. Common block-level Markdown (headings, lists, blockquotes) is automatically escaped and displays as literal text in labels.

See the body parameter of st.markdown for additional, supported Markdown directives.

For accessibility reasons, you should never set an empty label, but you can hide it with label_visibility if needed. In the future, we may disallow empty labels by raising an exception.

value (bool)

Preselect the checkbox when it first renders. This will be cast to bool internally.

key (str, int, or None)

An optional string or integer to use as the unique key for the widget. If this is None (default), a key will be generated for the widget based on the values of the other parameters. No two widgets may have the same key. Assigning a key stabilizes the widget's identity and preserves its state across reruns even when other parameters change.

A key lets you read or update the widget's value via st.session_state[key]. For more details, see Widget behavior.

Additionally, if key is provided, it will be used as a CSS class name prefixed with st-key-.

help (str or None)

A tooltip that gets displayed next to the widget label. Streamlit only displays the tooltip when label_visibility="visible". If this is None (default), no tooltip is displayed.

The tooltip can optionally contain GitHub-flavored Markdown, including the Markdown directives described in the body parameter of st.markdown.

on_change (callable)

An optional callback invoked when this checkbox's value changes.

args (list or tuple)

An optional list or tuple of args to pass to the callback.

kwargs (dict)

An optional dict of kwargs to pass to the callback.

disabled (bool)

An optional boolean that disables the checkbox if set to True. The default is False.

label_visibility ("visible", "hidden", or "collapsed")

The visibility of the label. The default is "visible". If this is "hidden", Streamlit displays an empty spacer instead of the label, which can help keep the widget aligned with other widgets. If this is "collapsed", Streamlit displays no label or spacer.

width ("content", "stretch", or int)

The width of the checkbox widget. This can be one of the following:

  • "content" (default): The width of the widget matches the width of its content, but doesn't exceed the width of the parent container.
  • "stretch": The width of the widget matches the width of the parent container.
  • An integer specifying the width in pixels: The widget has a fixed width. If the specified width is greater than the width of the parent container, the width of the widget matches the width of the parent container.

bind ("query-params" or None)

Binding mode for syncing the widget's value with a URL query parameter. If this is None (default), the widget's value is not synced to the URL. When this is set to "query-params", changes to the widget update the URL, and the widget can be initialized or updated through a query parameter in the URL. This requires key to be set. The key is used as the query parameter name.

When the widget's value equals its default, the query parameter is removed from the URL to keep it clean. A bound query parameter can't be set or deleted through st.query_params; it can only be programmatically changed through st.session_state.

Returns

(bool)

Whether or not the checkbox is checked.

Example

Python
import streamlit as st

agree = st.checkbox("I agree")

if agree:
    st.write("Great!")

Check out our video on how to use one of Streamlit's core functions, the checkbox! ☑

In the video below, we'll take it a step further and learn how to combine a button, checkbox and radio button!

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