microcharts vs MUI X Sparkline — bundle size and RSC comparison

MUI X Charts ships SparkLineChart — an inline-sized chart from the same family as its full Line, Bar, and Pie charts, themed by and integrated with Material UI. If your product is built on MUI and the sparkline sits in a MUI dashboard, that integration is a real advantage and this page may talk you out of nothing.

The comparison matters when the mark must be cheap, static, or independent of MUI: a table column of trends, a KPI row in an RSC, a chart in a streamed AI reply.

The numbers

MUI X sizes via esbuild tree-shake of @mui/x-charts/SparkLineChart, minify+gzip 2026-07-23; directive + default markup verified against the published package. microcharts from .size-limit.json (CI).

The two MUI scenarios are deliberate: inside a MUI app the Material core is already in your bundle, so the sparkline's marginal cost is the smaller figure. Without MUI, @mui/material and @mui/system are required peer dependencies — you install and ship them to render one sparkline.

Where the difference actually shows

Bundle cost. SparkLineChart shares MUI X's charting core (data providers, interaction plugins, vendored d3). That architecture is what makes the full chart family consistent — and it is why one sparkline carries tens of kilobytes. microcharts charges per chart subpath: 3.99 kB static · 6.64 kB interactive for Sparkline, catalog band ~2–7 kB interactive · ~1–4 kB static gzip.

Server Components. SparkLineChart is marked 'use client' — the server can emit initial HTML, but the component always hydrates and ships its JavaScript. The microcharts default export is hook-free static SVG with zero client JS; interactivity is a separate /interactive import.

Accessibility defaults. As published, the SparkLineChart SVG renders with aria-hidden="true" and no accessible name — the chart is invisible to assistive technology unless you label it yourself. Every microchart defaults to role="img" with a natural-language summary generated from the data.

Theming. MUI X charts theme through the MUI theme object — coherent if you live there. microcharts themes through --mc-* CSS custom properties at near-zero specificity, so it follows any design system, including a MUI one.

Reach for MUI X Sparkline

• Your app is already on MUI and the chart sits among MUI components
• You want one vendor for the sparkline and the full charts beside it
• You use MUI X's tooltip, highlighting, and animation stack elsewhere

Reach for microcharts

• The mark must not pull MUI (or anything) into the bundle — zero runtime dependencies
• You render from RSCs and want zero client JavaScript for static marks
• Accessibility should be the default, not a labeling task per chart
• You need chart types beyond sparklines at word size — 106 types, one grammar

What this page is not saying

• Not "MUI X is bloated" — the shared core is the price of a consistent full-chart family
• Not "never use SparkLineChart" — inside a MUI dashboard it is the coherent choice
• MUI X Charts (community) is MIT and actively maintained; the sizes are dated pins from the published package

Next

• When to use microcharts
• microcharts vs Recharts
• React sparklines
• Theming — fitting charts into an existing design system