Streamlit vs. NiceGUI: Choose the Best Python Web Framework

Compare Streamlit vs NiceGUI for Python web apps: architecture, customization, real-time behavior, and which framework fits your use case.

Streamlit vs. NiceGUI: Choose the Best Python Web Framework

Building web applications with Python doesn’t have to be complicated. Two frameworks make it especially easy: Streamlit and NiceGUI. Both let you create interactive web apps using mostly Python, but they shine in different scenarios.

Streamlit is optimized for data apps: dashboards, exploratory analysis, and ML demos. You write a Python script and Streamlit renders it as an app, with lots of built-in components for charts and tables.

NiceGUI is better suited for building application-style UIs (forms, admin panels, controls, monitoring tools). It’s built around a FastAPI server and a web UI layer, giving you more control over events, state, and backend capabilities.

Quick Comparison Overview

FeatureStreamlitNiceGUI
Best ForData apps, dashboardsGeneral web apps, desktop-like UIs
Learning CurveVery easyEasy
CustomizationLimitedHigh
BackendBuilt-inFastAPI
Real-time UpdatesAutomatic rerunsEvent-driven

For more Python web frameworks, see: Best Python Web Frameworks

Key Differences Between Streamlit and NiceGUI

1. Primary Purpose

  • Streamlit: Built specifically for data science, ML, and analytics dashboards
  • NiceGUI: Designed for general-purpose web applications with desktop-like interfaces

2. Development Approach

  • Streamlit: Script-based - runs from top to bottom on each interaction (often called “reruns”)
  • NiceGUI: Event-driven - responds to specific user actions

3. Customization Level

  • Streamlit: Limited customization, focuses on rapid prototyping
  • NiceGUI: Highly customizable with direct access to HTML/CSS/JS when needed

4. Backend Architecture

  • Streamlit: Built-in server runtime with session/state patterns
  • NiceGUI: FastAPI-based backend with more explicit control over routing and integration

5. Real-time Features

  • Streamlit: Interaction triggers a script rerun; you manage state/caching to keep it responsive
  • NiceGUI: Event-driven updates; good fit for “live UI” patterns (monitoring/control panels)

6. Learning Curve

  • Streamlit: Extremely beginner-friendly, no web dev knowledge needed
  • NiceGUI: Slightly steeper but still accessible, benefits from web dev basics

7. Community & Resources

  • Streamlit: Large community, extensive documentation, Streamlit Cloud hosting
  • NiceGUI: Growing community, good documentation, self-hosting focused

8. License & Cost

  • Streamlit: Apache 2.0, free with Streamlit Community Cloud (with limitations)
  • NiceGUI: MIT License, completely free and open source

When to Choose Each Framework

Choose Streamlit if you need:

  • Data dashboards with charts, tables, and visualizations
  • ML model interfaces for demos and prototypes
  • Rapid development with minimal coding
  • Built-in data handling (CSV, JSON, databases)
  • Easy deployment on Streamlit Cloud

Example use cases:

  • Sales analytics dashboard
  • Machine learning model demo
  • Financial data explorer
  • Research data visualization

Choose NiceGUI if you need:

  • Desktop-like applications in the browser
  • Real-time interactions without page reloads
  • Custom UI components and layouts
  • Advanced backend features (authentication, APIs)
  • Full control over user experience

Example use cases:

  • Project management tools
  • IoT device controllers
  • Interactive forms and surveys
  • Real-time monitoring systems

Getting Started: Code Examples

Both frameworks are beginner-friendly, but Streamlit has a slight edge for absolute beginners.

Streamlit Example: Data Dashboard

import streamlit as st
import pandas as pd

st.title('Sales Dashboard')

data = pd.DataFrame({
    'Month': ['Jan', 'Feb', 'Mar', 'Apr'],
    'Sales': [100, 150, 120, 200],
})

month_filter = st.selectbox('Select Month', data['Month'])
filtered = data[data['Month'] == month_filter]

st.bar_chart(data.set_index('Month'))
st.write(f'Sales for {month_filter}: ${int(filtered["Sales"].iloc[0])}')

NiceGUI Example: Interactive Form

from nicegui import ui

def handle_submit():
    ui.notify(f'Hello {name.value}! You are {age.value} years old.')

ui.label('User Information Form')

with ui.row():
    name = ui.input('Name', placeholder='Enter your name')
    age = ui.number('Age', value=25, min=0, max=120)

ui.button('Submit', on_click=handle_submit)

ui.run()

Key Differences in the Code:

  • Streamlit: Linear, script-like flow - perfect for data workflows
  • NiceGUI: Component-based with explicit event handling - better for interactive apps

NiceGUI Advantages

Real-Time Interactions

  • Event/callback-driven UI updates
  • Good fit for monitoring, controls, and “app-like” UIs

FastAPI Integration

  • You can take advantage of FastAPI concepts (routing, dependencies, middleware) as your app grows
  • Useful when you need APIs alongside the UI, or want more control over auth and request handling

Note: “built-in authentication and user management” isn’t automatic in FastAPI itself. You typically implement auth using FastAPI patterns and libraries, then integrate it with your app.

Advanced Customization

  • More layout and component control than Streamlit
  • Can integrate with web concepts when needed (styling and custom behavior)

Development Experience

  • Good local dev workflow and straightforward self-hosting
  • Works well in containers when you need repeatable deployment

Flexibility

  • Natural fit for event-driven apps
  • Can integrate with existing Python services and libraries

Streamlit Advantages

Data Apps First

  • Excellent defaults for pandas DataFrames, charts, and common analytics workflows
  • Great for ML demos and internal dashboards

Ultra-Simple Development Model

  • Very low “web framework” overhead: write Python top-to-bottom
  • Easy to iterate quickly and share prototypes with teammates

Deployment Options

  • Streamlit Community Cloud is convenient for quick publishing
  • Also deployable to your own infrastructure (VPS, containers, etc.)

Data-Focused Widgets

  • Strong widget set for filters, inputs, and interactive exploration
  • Built-in caching and session state patterns help keep apps responsive

Strong Ecosystem

  • Large community, lots of examples and integrations

Making Your Choice: Decision Guide

Choose Streamlit if:

  • ✅ You’re building data dashboards or ML demos
  • ✅ You want rapid prototyping with minimal code
  • ✅ You’re new to web development
  • ✅ You need built-in data visualization
  • ✅ You want easy deployment and sharing

Choose NiceGUI if:

  • ✅ You need real-time interactions without page reloads
  • ✅ You’re building general-purpose web apps
  • ✅ You want desktop-like UI in the browser
  • ✅ You need advanced backend features
  • ✅ You want full customization control

Quick Start Resources

Streamlit:

NiceGUI:

Final Verdict

Both frameworks excel in their domains. Streamlit dominates data science applications with its simplicity and built-in data tools. NiceGUI shines for interactive web applications that need desktop-like functionality.

The best choice depends on your project requirements, not on which framework is “better” overall. Start with the one that matches your immediate needs - you can always explore the other later as your projects evolve.