YUI, the Yahoo User Interface library, is no longer developed. Yahoo announced on August 29, 2014 that it would immediately stop all new development, and the last release, YUI 3.18.1, followed on October 22, 2014. InfoQ's report on the decision quotes Yahoo saying further fixes would cover only issues critical to Yahoo's own sites. The code still installs from npm, and the docs mirror still loads with a notice that the library is no longer actively maintained.
So the real question is what to put in its place. YUI bundled three things: a module loader and DOM utilities, a widget set (Calendar, DataTable, AutoComplete, TreeView, Rich Text Editor), and CSS for reset, fonts and grids. Today those come from different tools. Browsers and npm cover the loader and utilities. The picks below replace the widgets and the app structure. For the CSS part, Yahoo's own follow-up was Pure, which our Pure CSS alternatives guide covers in detail.
The order runs from the least disruptive replacement for a page full of YUI widgets to the full rewrites, with a legacy stopgap at the end.
Prices below are as of November 8, 2026. Our method is on How we review tools.
Quick comparison
| Tool | Best for | Price | Platforms |
|---|---|---|---|
| Lit | Framework-free components you build | Free (BSD-3-Clause) | Any modern browser, any framework |
| Web Awesome | Ready-made widgets without a framework | Free core; Pro billed yearly | Any modern browser, npm or download |
| React with MUI | Data-heavy apps that need a grid | Free; MUI X Pro from $299/dev/year | React 17, 18, 19 |
| Vue | Adding interactivity page by page | Free (MIT) | Browser; Node for builds |
| Angular | Large apps with one way of doing things | Free (MIT) | Browser; Node 22.22+ for the CLI |
| Svelte | Small bundles, compiled components | Free (MIT) | Browser; SvelteKit on Node 22.17+ |
| jQuery UI | Patching a legacy page short term | Free (MIT) | Any browser jQuery 4 supports |
Lit
Lit comes closest to the original YUI idea: load a small piece of code, get a widget that works on any page. It builds on the Web Components standards, so a calendar element you write with Lit runs inside React, Vue, a server-rendered template or plain HTML. The Lit site puts the library at around 5 KB minified and compressed.
lit 3.3.3 was published on May 14, 2026 under the BSD-3-Clause licence, the same licence family YUI used. The project now belongs to the OpenJS Foundation rather than a single company. Server rendering ships separately as @lit-labs/ssr, currently 4.1.0.
Best for: Teams replacing YUI widgets one at a time on pages that mix several stacks.
Pricing:
- Free, BSD-3-Clause licence
- No paid tier
Watch out for:
- Lit is a way to build components, not a finished set of them. You still have to write or source the date picker, data table and tree view that YUI used to include.
- Server rendering sits outside the core package, under the labs scope shown on the @lit-labs/ssr npm entry. It has its own version line: 4.1.0, while core Lit is on 3.3.3.
Official site: Lit.
Web Awesome
Web Awesome is what the Shoelace project became, and it is the nearest thing to a drop-in YUI widget catalogue today. It has 50+ components, most of them free, plus themes, CSS utilities, page layouts and localization, all as web components you load from npm or a direct download. It is published by Fonticons, Inc., the company behind Font Awesome.
Version 3.0.0 shipped on October 28, 2025 and 3.14.0 on September 24, 2026. The old @shoelace-style/shoelace package stopped at 2.20.1 in March 2025, so new work should start on Web Awesome rather than Shoelace.
Best for: Sites that want finished, styled widgets without committing to React, Vue or Angular.
Pricing:
- 50+ components, most of them free
- Pro: per-seat yearly subscription (price not published)
- 5 or more seats: price on request
- Pro includes a perpetual licence
Watch out for:
- The widgets YUI users miss most are in the paid tier. Combobox, Date Picker, File Input, charts and the Data Grid are listed as Pro-only components.
- Pro is a yearly subscription per seat that renews until cancelled, according to the Web Awesome purchase page.
Official site: Web Awesome.
React with MUI
If the YUI app is being rewritten rather than patched, React with MUI covers most of the old widget list in one dependency tree. Material UI 9.5.0, from October 9, 2026, ships 40+ free components under MIT and supports React 17, 18 and 19. React itself is at 19.3.1, published October 14, 2026.
The YUI DataTable has a clear successor in the MUI X Data Grid. Its free Community edition, 9.17.0 from October 30, 2026, is MIT-licensed and handles sorting, filtering, pagination and editing. Advanced features such as tree data, row grouping and pivoting are sold under the Pro and Premium licences.
Best for: Admin panels and internal tools where the data grid is the main screen.
Pricing:
- Community: free, MIT
- Pro: $299 per developer per year (billed yearly)
- Premium: $599 per developer per year (billed yearly)
- Enterprise: $1,399 per developer per year, from 15 seats
Watch out for:
- Majors arrive quickly. Material UI 7.0.0 shipped in March 2025 and 9.0.0 in April 2026, and 10.0.0-alpha.0 was already on npm's next tag on October 12, 2026.
- Annual MUI X licences need an active subscription for development work, and the MUI pricing page allows renewal increases of up to 7%.
Official site: React with MUI.
Vue
Vue suits YUI shops that liked adding behaviour to server-rendered pages one region at a time. You can mount a Vue app on a single element, then grow it into a full single-page app with the official router (vue-router 5.4.0) and the Pinia store (4.1.0) when the project needs them.
Vue 3.5.45 was published on November 5, 2026, MIT-licensed, and 3.6.0-rc.14 has been on the rc tag since October 30, 2026. The 3.x API dates back to September 2020, so the core concepts have been stable for six years.
Best for: Progressive rewrites where old and new code share the same page for a while.
Pricing:
- Free, MIT licence
- No paid tier from the core team
Watch out for:
- The last major move was costly for many teams. Vue 2 reached end of life on December 31, 2023, per the Vue 2 LTS page, and support after that date is a paid third-party product from HeroDevs.
Official site: Vue.
Angular
Angular is the full-framework answer. It replaces YUI's App Framework, which had models, views and a router, more than the widget library. The router, forms and HTTP client are first-party packages, and the CLI (22.2.6, November 4, 2026) generates and builds projects.
From version 22, Angular moved to one major release a year, with 12 months of active support followed by 12 months of LTS. Angular 22.0.0 shipped on June 3, 2026, so its LTS runs to June 2028. @angular/core 22.2.5 is the current release, from November 6, 2026.
Best for: Large teams that want one prescribed structure for a long-lived app.
Pricing:
- Free, MIT licence
- No paid tier
Watch out for:
- The 22.x CLI accepts only Node ^22.22.3, ^24.15.0 or 26 and newer, per its npm engines field, so older build servers need an upgrade first.
- Older majors drop off on a fixed date: Angular 20 leaves LTS on November 28, 2026, according to the Angular release schedule.
Official site: Angular.
Svelte
Svelte is a compiler. You write components in .svelte files and the build step turns them into JavaScript that updates the page directly, which keeps bundles small for widget-sized features. That suits a YUI page where you want to replace one TabView or Slider without shipping a large framework next to it.
Svelte 5.0.0 arrived on October 19, 2024, and 5.57.3 is current (October 26, 2026), MIT. SvelteKit 3.1.1 adds routing and server rendering and needs Node 22.17 or newer, while the 2.x line still gets patches, with 2.70.4 on November 5, 2026.
Best for: Lightweight interactive pieces where bundle size matters.
Pricing:
- Free, MIT licence
- No paid tier
Watch out for:
- Svelte 5 replaced implicit reactivity with runes such as $state and $props. The old syntax still works, but the Svelte 5 migration guide marks createEventDispatcher as deprecated, so many older tutorials teach a style the docs are moving away from.
Official site: Svelte.
jQuery UI
jQuery UI earns a place for one reason: many YUI 2 pages already load jQuery, and its 14 widgets map closely onto the YUI ones. Datepicker stands in for Calendar, Autocomplete for AutoComplete, and Menu, Slider, Tabs and Dialog cover the rest of the common set.
Version 1.14.2 shipped on January 28, 2026 and was tested against jQuery 1.12.4 through 4.0.0. jQuery 4.0.0 itself came out on January 18, 2026, and jQuery UI 1.14 no longer supports IE or legacy Edge.
Best for: A short-term rescue of a legacy page, not a new build.
Pricing:
- Free, MIT licence
Watch out for:
- The project is in a maintenance state. The jQuery UI 1.14.2 release post says no significant feature work is planned and older long-standing bugs may not get fixed.
- There is no data grid, tree view or rich text editor, so YUI DataTable, TreeView and Editor pages need another library anyway.
Official site: jQuery UI.
How to choose
| If you need | Pick |
|---|---|
| Replace YUI widgets one by one on mixed pages | Lit |
| Finished widgets without adopting a framework | Web Awesome |
| A serious data grid to replace YUI DataTable | React with MUI |
| Move a server-rendered site over gradually | Vue |
| A long-lived app with fixed support dates | Angular |
| The smallest bundles for interactive pieces | Svelte |
| Buy time on a page that already loads jQuery | jQuery UI |
When to stay with YUI
Keep YUI only for an internal app that is frozen and already scheduled for retirement. YUI 3.18.1 still installs from npm and the YUI library docs still load, but nobody is shipping security fixes, and the code predates every browser API the alternatives rely on. Anything public-facing should move.
Frequently asked questions
Is YUI still supported?
No. Yahoo stopped all new development on August 29, 2014 and limited later fixes to issues critical to Yahoo properties. The final release is 3.18.1 from October 22, 2014, and the yui package on npm has not changed since.
Why did Yahoo stop developing YUI?
Yahoo's announcement pointed to how JavaScript had changed. Node.js moved JavaScript to the server, npm and Bower created an ecosystem of small single-purpose packages, build tools such as Grunt and Gulp assembled them, and frameworks like React, Angular and Ember gave apps their structure. Yahoo also said many developers now saw large libraries as walled gardens.
What replaced YUI CSS Reset, Fonts and Grids?
Yahoo's later CSS project was Pure, a set of small CSS modules released under the Yahoo BSD licence. Pure 3.1.0 was published on September 28, 2026 and the whole set is 3.5KB minified and gzipped. Modern browsers also cover most of the old YUI Grids job with native CSS Grid and Flexbox.
Can I still download YUI?
Yes. The yui package on npm holds version 3.18.1 under the BSD licence, and the docs mirror still offers the same build. Use it to keep an old app running while you migrate, not to start anything new.
