As apps grow large, it becomes useful to organize them into multiple pages. This makes the app easier to manage as a developer and easier to navigate as a user. Streamlit provides a frictionless way to create multipage apps. Pages are automatically shown in a nice navigation widget inside the app sidebar, and clicking on a page will navigate to the page without reloading the frontend — making app browsing incredibly fast!
We created a "single-page app" to explore a public Uber dataset for pickups and drop-offs in New York City on the previous page. In this guide, let’s learn how to create multipage apps. Once we have a solid foundation on what it takes to create multipage apps, let’s build one for ourselves in the next section!
Structuring multipage apps
Let's understand what it takes to create multipage apps — including how to define pages, structure and run multipage apps, and navigate between pages in the user interface. Once you've understood the basics, you can jump right into the next section to convert the familiar
streamlit hello command into a multipage app!
Run a multipage app
Running a multipage app is identical to running a single-page app. The command to run a multipage app is:
streamlit run [entrypoint file]
The "entrypoint file" is the first page the app will show to the user. Once you have added pages to your app, the entrypoint file appears as the top-most page in the sidebar. You can think of the entrypoint file as your app's "main page". For example, say your entrypoint file is
Home.py. Then, to run your app, you can run
streamlit run Home.py. This will start your app and execute the code in
Once you've created your entrypoint file, you can add pages by creating
.py files in a
pages/ directory relative to your entrypoint file. For example, if your entrypoint file is
Home.py, then you can create a
pages/About.py file to define the "About" page. Here's a valid directory structure for a multipage app:
Home.py # This is the file you run with "streamlit run" └─── pages/ └─── About.py # This is a page └─── 2_Page_two.py # This is another page └─── 3_😎_three.py # So is this
When adding emojis to filenames, it’s best practice to include a numbered-prefix to make autocompletion in your terminal easier. Terminal-autocomplete can get confused by unicode (which is how emojis are represented).
Pages are defined as
.py files in a
pages/ directory. The filenames of pages are transformed to page names in the sidebar based on the the rules in the section below. For example, the
About.py file will appear as "About" in the sidebar,
2_Page_two.py appears as "Page two", and
3_😎_three.py appears as “😎 three”:
.py files in the
pages/ directory will be loaded as pages. Streamlit ignores all other files in the
pages/ directory and subdirectories.
How pages are labeled and sorted in the UI
Page labels in the sidebar UI are generated from filenames. They may differ from the page title set in
st.set_page_config. Let's learn what constitutes a valid filename for a page, how pages are displayed in the sidebar, and how pages are sorted.
Valid filenames for pages
Filenames are composed of four different parts:
number— if the file is prefixed with a number.
- A separator — could be
-, space, or any combination thereof.
label— which is everything up to, but not including,
- The extension — which is always
How pages are displayed in the sidebar
What is displayed in the sidebar is the
label part of the filename:
- If there's no
label, Streamlit uses the
numberas the label.
- In the UI, Streamlit beautifies the
How pages are sorted in the sidebar
Sorting considers numbers in the filename to be actual numbers (integers):
- Files that have a
numberappear before files without a
- Files are sorted based on the
number(if any), followed by the
- When files are sorted, Streamlit treats the
numberas an actual number rather than a string. So
03is the same as
This table shows examples of filenames and their corresponding labels, sorted by the order in which they appear in the sidebar.
|hello dear world|
Emojis can be used to make your page names more fun! For example, a file named
🏠_Home.py will create a page titled "🏠 Home" in the sidebar.
Navigating between pages
Pages are automatically shown in a nice navigation UI inside the app's sidebar. When you click on a page in the sidebar UI, Streamlit navigates to that page without reloading the entire frontend — making app browsing incredibly fast!
You can also navigate between pages using URLs. Pages have their own URLs, defined by the file's
label. When multiple files have the same
label, Streamlit picks the first one (based on the ordering described above). Users can view a specific page by visiting the page's URL.
If a user tries to access a URL for a page that does not exist, they will see a modal like the one below, saying the user has requested a page that was not found in the app’s pages/ directory.
Pages support magic commands.
Pages support run-on-save. Additionally, when you save a page, this causes a rerun for users currently viewing that exact page.
Adding or deleting a page causes the UI to update immediately.
Updating pages in the sidebar does not rerun the script.
st.set_page_configworks at the page level. When you set a title or favicon using st.set_page_config, this applies to the current page only.
Pages share the same Python modules globally:
# page1.py import foo foo.hello = 123 # page2.py import foo st.write(foo.hello) # If page1 already executed, this should write 123
Pages share the same st.session_state:
# page1.py import streamlit as st if "shared" not in st.session_state: st.session_state["shared"] = True # page2.py import streamlit as st st.write(st.session_state["shared"]) # If page1 already executed, this should write True
You now have a solid understanding of multipage apps. You've learned how to structure apps, define pages, and navigate between pages in the user interface. It's time to create your first multipage app! 🥳