Plotly creates interactive (zoomable, hoverable) charts in the browser. v6.0 (2025) drops big dependencies (Pandas is optional) and improves performance.
When to Use
Dashboards: Streamlit, Dash.
3D Plots: Rotating 3D scatter plots.
Interactivity: Users need to drill down into data.
Core Concepts
Plotly Express (
px
)
High-level API.
px.scatter(df, x="a", y="b", color="c")
.
Graph Objects (
go
)
Low-level API.
go.Figure(data=[go.Scatter(...)])
.
Dash
The framework for building web apps with Plotly charts.
Best Practices (2025)
Do:
Use Plotly Express: It covers 90% of use cases.
Use WebGL:
render_mode='webgl'
for large datasets (>10k points).
Don't:
Don't use it for static papers: Use Matplotlib for print.