plotly-print

Export Plotly figures to SVG, PNG, JPEG, or WebP without launching Chrome.

plotly-print runs a bundled Plotly.js 2D build in QuickJS, then uses resvg-py for raster output. It works offline, has no browser process to install or manage, and can replace Plotly's image-export methods with one call.

• Browser-free: no Chrome, Chromium, or Playwright.
• Fast: avoids browser startup; see the measured benchmarks.
• Familiar: use the direct API or patch Plotly's existing to_image and write_image methods.

Install | Direct API | Plotly integration | Benchmarks

Installation

pip install plotly-print

Requires Python 3.12 or newer.

Direct API

import plotly.express as px
import plotly_print

fig = px.scatter(x=[1, 2, 3, 4], y=[10, 11, 12, 13], title='Sales Growth')

svg = plotly_print.to_svg(fig)
png = plotly_print.to_image(fig, format='png', scale=2)
plotly_print.write_image(fig, 'chart.png')

to_image returns bytes. write_image writes to a path or binary file object. Supported formats are SVG, PNG, JPEG, and WebP.

Plotly integration

Patch Plotly's existing image-export methods:

import plotly_print

plotly_print.register()

After registration, existing calls such as fig.write_image("chart.png") use plotly-print. Call plotly_print.unregister() to restore Plotly's original methods.

plotly-print targets 2D static charts. The bundled Plotly.js build and its licenses are documented in THIRD_PARTY_NOTICES.md.

Benchmarks

On this run, plotly-print exported all 29 chart types 11x to 33x faster than Kaleido.

These are mean per-image PNG export times after both engines were warmed up. Timings are machine-specific; use the side-by-side images below to evaluate rendering differences.

See the raw results or run the benchmark locally.

Visual comparisons

Side-by-side PNGs (Kaleido left, plotly-print right):

Core Cartesian

Scatter & Line Chart (plotly-print: 88.9ms | Kaleido: 1524.7ms)

Grouped Bar Chart (plotly-print: 93.5ms | Kaleido: 1642.3ms)

Donut / Pie Chart (plotly-print: 74.4ms | Kaleido: 1812.6ms)

Box Plot (plotly-print: 93.5ms | Kaleido: 1714.4ms)

Violin Plot (plotly-print: 86.5ms | Kaleido: 1626.1ms)

Frequency Histogram (plotly-print: 105.5ms | Kaleido: 1556.6ms)

2D Density Histogram (plotly-print: 105.5ms | Kaleido: 1696.5ms)

2D Contour Plot (plotly-print: 135.8ms | Kaleido: 1744.5ms)

Performance Heatmap (plotly-print: 95.4ms | Kaleido: 1647.1ms)

Ternary Phase Diagram (plotly-print: 95.8ms | Kaleido: 1639.1ms)

Financial & Business

Candlestick Stock Chart (plotly-print: 125.6ms | Kaleido: 1618.5ms)

OHLC Financial Chart (plotly-print: 159.2ms | Kaleido: 1686.0ms)

Waterfall Profit & Loss (plotly-print: 67.1ms | Kaleido: 1561.6ms)

Sales Conversion Funnel (plotly-print: 102.3ms | Kaleido: 1620.2ms)

Funnel Area Analysis (plotly-print: 59.2ms | Kaleido: 1593.7ms)

KPI Performance Indicator (plotly-print: 69.9ms | Kaleido: 1607.4ms)

Hierarchical

Market Cap Treemap (plotly-print: 52.9ms | Kaleido: 1672.0ms)

Global Sunburst Hierarchy (plotly-print: 69.8ms | Kaleido: 1665.6ms)

Icicle Partition Chart (plotly-print: 59.8ms | Kaleido: 1662.9ms)

Radial & Polar

Radar Performance Comparison (plotly-print: 98.2ms | Kaleido: 1689.3ms)

Polar Wind Rose (plotly-print: 78.3ms | Kaleido: 1581.8ms)

Specialized Diagrams

Energy Flow Sankey Diagram (plotly-print: 47.6ms | Kaleido: 1593.5ms)

Parallel Categories Diagram (plotly-print: 68.7ms | Kaleido: 1551.1ms)

Formatted Data Table (plotly-print: 96.7ms | Kaleido: 1588.6ms)

Carpet Coordinate Plot (plotly-print: 99.5ms | Kaleido: 1647.8ms)

Layout edge cases

Bar chart with X labels at 45 deg (plotly-print: 92.5ms | Kaleido: 1741.8ms)

Bar chart with X labels at 90 deg (plotly-print: 101.8ms | Kaleido: 1609.2ms)

Annotation arrowheads (incl. circle) (plotly-print: 86.5ms | Kaleido: 1663.2ms)

Long annotation arrows (dasharray length) (plotly-print: 93.3ms | Kaleido: 1650.6ms)

Attribution

plotly-print is an independent project derived from Mirage by Benjamin Lear (MIT). Bundled plotly.js is copyright Plotly, Inc. (MIT); see THIRD_PARTY_NOTICES.md.