Material UI -- a React component library implementing Google's Material Design. Buttons, dialogs, tables, theming, the lot.
Alternative to: Telerik KendoReact at $649-$1,199 per developer per year on subscription, and Tailwind Plus at $299 one-time for a personal licence or $979 for a team of up to 25. The closer comparison is MUI's own paid line: MUI X Pro at $299/developer/year and MUI X Premium at $599/developer/year.
Cost to run: free. No licence fee, no seat count, no application count. The costs that remain are bundle weight, a runtime CSS-in-JS engine, and migration labour.
Licence: MIT. Free for commercial use. The repo's own tagline is "Free forever."
Runs on: React 17, 18 or 19. Next.js App Router and Pages Router via the separate@mui/material-nextjsadapter.
Requires: react, react-dom, and@emotion/reactplus@emotion/styledas peer dependencies. Not React Server Component--native: Material UI components are Emotion-based client components and need"use client".
Traction: 98,850 stars · 32,600 forks · 3,130 contributors · 28,541 commits · 1,377 open issues / 19,130 closed · 8,703,878 npm downloads in the week of 9-15 August 2026.
Liveness: very live -- last commit 2026-08-17, patch releases landing every one to two weeks.
Maturity: v9.3.1, released 2026-08-06. Material UI v9.0 shipped 2026-04-08 and skipped v8 entirely to sync major versions with MUI X. In the project's own words: "Material UI moves from v7 straight to v9 (there is no Material UI v8, like there is no v2)."
Links: repo · mui.com · Trendshift peak #1, 2025-11-09
Figures as of 2026-08-18.
What it does
Material UI gives a React application a full set of interface components that already look finished. You import a Button or a Dialog or a DataGrid, and it arrives styled, accessible, themed and responsive, following Google's Material Design rules.
The value is not that it draws a button. It is that somebody already argued about focus rings, keyboard navigation, right-to-left layouts, dark mode, and what a date picker does on a phone -- and shipped the answer. A team adopting it skips a design system it would otherwise have to build and maintain.
It is also, by download volume, one of the most-used front-end packages in existence: 8.7 million downloads in a single week, and 41.4 million over the trailing thirty days.
The styling engine underneath is Emotion, which generates CSS at runtime. That single fact drives most of the criticism in this entry.
What it replaces, and what that costs
Two different comparisons matter here, and conflating them would be dishonest.
The first is commercial component libraries -- the things a team buys instead of adopting an open-source one.
Telerik KendoReact -- $649 to $1,199 per developer per year depending on discount tier. The broader multi-framework Kendo UI bundle runs $799 to $1,299 per developer per year.
Tailwind Plus, formerly Tailwind UI -- a one-time purchase, not a subscription. Personal licence $299; Team licence, up to 25 people, $979. Lifetime access, future updates included.
Syncfusion Essential Studio -- per developer, quote-based rather than a published flat number.
Against those, Material UI Core costs nothing. For a five-developer team over one year:
KendoReact at the top tier -- 5 × $1,199 = $5,995
KendoReact at the entry tier -- 5 × $649 = $3,245
Tailwind Plus Team -- $979 once, covering up to 25
Material UI Core -- $0
The second comparison is MUI's own paid tier, and it is the one that decides real projects. MUI Core is MIT and always has been. MUI X -- the advanced Data Grid, Charts, Date Pickers and Scheduler -- is not.
MUI X Pro: $299 per developer per year ($24.92/month). Unlocks the Pro Data Grid: column pinning, row pinning and reordering, advanced filtering.
MUI X Premium: $599 per developer per year ($49.92/month). Adds pivoting, aggregation, row grouping and Excel export.
MUI X Enterprise: $1,399 per developer per year, 15-seat minimum. As of the April 2026 pricing change, Enterprise is the only tier that carries priority support.
That same five-developer team, if it needs Excel export from a grid: 5 × $599 = $2,995 a year.
One licensing detail is easy to miss and expensive to get wrong. On 2026-04-08 MUI moved Pro and Premium to application-based licensing, with separate single-app and multi-app options. If you are scoping cost by headcount alone, check the app count.
So: adopting Material UI Core avoids a licence bill entirely, and that is a real avoided cost against KendoReact or Syncfusion. It does not avoid the MUI X bill, because MUI X is a different product solving a different job. Nothing about installing the free library reduces what the Pro data grid costs. Those two numbers do not subtract.
Is it still alive?
Very live, with an honest asterisk.
The last commit landed 2026-08-17, about fifteen hours before these figures were taken. Material UI v9.0 shipped on 2026-04-08 as a coordinated relaunch across the whole MUI product line, and patch releases are arriving every week or two -- v9.3.1 came six days after v9.3.0. Recent issues carry maintainer-applied scope and status labels, and named MUI engineers are filing RFCs within the last few weeks.
The asterisk: 1,377 open issues against 19,130 closed. That is a large backlog. It is normal for a project at this scale and it is not evidence of neglect, but a directory that only reported the good number would be lying by omission.
Trendshift records the repo reaching #1 on GitHub Trending on 2025-11-09.
What people say
Reddit is unreachable from the research sandbox, so the highly relevant r/reactjs and r/nextjs threads are named but not quoted. Hacker News comments below carry permalinks; HN does not display per-comment scores, so none are claimed.
The dissent first, because it is the loudest thing in this repo's orbit:
"Every Material UI library I've seen in existence is a bloated wreck full of bugs... I wish Material UI would either get significantly better or just die already."
-- WorldMaker, news.ycombinator.com/item?id=44005749
A more measured version of the same argument, in the same thread:
"I tend to agree with your criticisms. FWIW, I do think mui has peaked, at least for greenfield projects. A new wave of tailwind-based libraries are rising fast, the most prominent of which are Mantine and Shadcn. IME, both perform MUCH MUCH better than mui."
-- Octoth0rpe, news.ycombinator.com/item?id=44006336
And the case for it, from a thread on building an internal component library:
"Libraries like Material UI are battle tested and cover the vast majority of components you're going to need. You can extend or theme them to match your needs and often include a built in design system. The likelihood of building something better from scratch are low."
-- mindfulmark, news.ycombinator.com/item?id=41607286
The catch
Runtime CSS-in-JS is the recurring complaint, and the fix is stalled. Pigment CSS was MUI's answer -- zero-runtime styling, no Emotion dependency. Maintainer Olivier Tassinari, on the open tracking issue, 2025-03-31:
"In the current trajectory Pigment CSS is in, it feels like we would need a miracle to fix 1., 2., 3. soon enough to be used in the next major of Material UI, so I don't think it's realistic."
The v9 announcement instead promises to "explore refactoring the styling layer" in a future major, targeting "independence from Emotion and better integration paths for teams using Tailwind CSS." That is a plan, not a shipped fix.
It is not RSC-native. Material UI components are client components. The @mui/material-nextjs adapter exists specifically to make the App Router workable via a cache provider. Compared with copy-in, server-renderable alternatives, that is friction you inherit on day one.
The version numbers lie to you. v7 is followed by v9. There is no v8. This is documented and deliberate, and it still catches people.
The data grid wall is real. Column pinning, row pinning and reordering sit behind Pro at $299/dev/year. Pivoting and Excel export sit behind Premium at $599.
MUI Toolpad is not actively maintained, per the banner on its own repository. If you were evaluating MUI's low-code admin story specifically, that is the answer.
Credits
Olivier Tassinari (oliviertassinari), MUI co-founder, whose own assessment of Pigment CSS is quoted above. José Freitas (joserodolfofreitas), co-author of the v9 announcement. MUI (@MUI_hq) and the 3,130 contributors on the repo. The Hacker News commenters quoted above. Download figures from the npm registry API; pricing verified against MUI, Telerik, Tailwind and Syncfusion's own pages; peak rank from Trendshift.