WebSpatial

WebSpatial
Information
Type	Software development kit
Industry	Spatial computing
Developer	WebSpatial project (PICO, ByteDance)
Written In	TypeScript, Swift
Operating System	visionOS (packaged apps), PICO OS 6 (built-in runtime)
License	MIT License
Supported Devices	Apple Vision Pro; devices running PICO OS 6
Release Date	July 7, 2025 (version 1.0.0)
Website	https://webspatial.dev/

WebSpatial is an open-source project that adds a small set of spatial extensions to HTML, CSS and DOM APIs, together with a software development kit (the WebSpatial SDK) that lets developers use those extensions in React web projects before browsers implement them natively. Its documentation describes it as "a set of minimal extensions to HTML/CSS/DOM APIs plus a polyfill-style open-source SDK". With it, parts of an ordinary website can be lifted off the page plane, given depth, combined with 3D models and dynamic 3D content, and made to respond to spatial gestures when the site runs on a spatial computing platform, while the same site behaves as a normal web page in desktop and phone browsers.

The project was presented by staff of PICO, a subsidiary of ByteDance, at AWE USA 2025 and at the W3C's TPAC 2025 meeting, and PICO named it as the web development path for its PICO OS 6 operating system when that system was announced on 2 March 2026. As of October 2026 the documentation lists two supported platforms: visionOS on the Apple Vision Pro, where a site is packaged as a native app, and PICO OS 6, whose system web app runtime includes WebSpatial support. The code is published on GitHub under the MIT License.

Reviewed 15 October 2026. Checked the WebSpatial docs, GitHub repository and release tags, AWE 2025 listing, W3C TPAC 2025 issue, slides and recap, and PICO OS 6 coverage (PICO release, heise, UploadVR, MoguraVR, Road to VR) against every claim. About review dates.

History

Early releases (2025)

The earliest releases listed in the project's GitHub repository date from March 2025, starting with version 0.0.8 of the React SDK package on 11 March 2025; the first listed release of the Core SDK package, version 0.0.2, followed on 19 March 2025. The documentation for that period, now kept as the legacy 1.0.x handbook, told developers that "The WebSpatial SDK is newly open-sourced and may have bugs or missing docs/examples", and its setup instructions were written around Apple Vision Pro, Xcode and the visionOS simulator.

At AWE USA 2025, Ruoya Sheng of PICO gave a developer-track talk on 11 June 2025 titled "Empower Developers - Bring Web and AI to Spatial". The session listing described WebSpatial as "an open-source framework that brings standard websites into XR", usable "without needing Unity or WebXR", and presented it alongside SecureMR, a separate PICO runtime for on-device AI. Version 1.0.0 of the Core SDK and React SDK packages was tagged on 7 July 2025; the Core SDK changelog entry reads "first major version".

W3C proposal (TPAC 2025)

On 29 September 2025 a breakout session titled "WebSpatial API for Spatialized HTML/CSS and Spatialized PWAs on spatial and multimodal AI devices" was proposed for TPAC 2025, the W3C's annual meeting. A follow-up comment on the proposal stated that it was "proposed by ByteDance Pico". The proposal argued that the WebXR standard, which takes over the whole display and renders its content independently, could not meet the needs of operating systems that render several apps together in a shared space, and suggested extending existing HTML, CSS and Progressive Web App technology with a minimal set of new APIs instead.

The presentation was given by Dexter Yang, Ruoya Sheng and Siyaman Sadagopan, listed on the slides as members of the "PICO OS, ByteDance" team, at TPAC 2025 in Kobe, Japan (10-14 November 2025). The W3C published the slides as a PDF, and its later recap of the 85 breakout sessions held at TPAC 2025 grouped the WebSpatial session under AI topics. The slides said that, without such APIs, web developers building for AR glasses, visionOS and Android XR would be pushed toward native GUI stacks or toward hybrid ecosystems such as React Native and "mini-apps" that diverge from the mainstream web.

PICO OS 6 announcement (2026)

When PICO unveiled PICO OS 6 and previewed its Project Swan headset on 2 March 2026, its press release said the company was "democratizing spatial app creation with WebSpatial", which it described as an open-source framework bringing HTML, CSS and React to spatial computing. PICO said the framework would let developers build "install-free, cross-platform apps" running on PICO OS, visionOS and Android XR. UploadVR reported that PICO called WebSpatial an "open, minimal extension to HTML, CSS, and JS". heise online reported that the framework lets developers create 3D web apps with HTML, CSS and React and anchor them in space alongside 2D and 3D applications, and that PICO described it as cross-platform, able to run on PCs, mobile devices and other spatial systems such as visionOS and Android XR. The Japanese outlet MoguraVR also reported the framework's release as part of PICO's new developer tools.

The project's documentation lists fewer supported platforms than PICO's announcement. As of October 2026 it lists Android XR and Meta Horizon OS as platforms "planned for priority support, but currently waiting for stable native APIs", and the JSAR Runtime (used on Rokid glasses) and IRIS OS as platforms still working toward a WebSpatial runtime. The headset previewed as Project Swan, later named PICO Space Pro, had not been released by September 2026, when PICO cancelled a planned 2 September reveal and postponed its launch to the fourth quarter of 2026.

Version 2

Version 2.0.0 of the SDK packages was released on 21 August 2026. The React SDK's default entry point now loads spatial code lazily: spatial UI is mounted behind a SpatialBoot component, and the spatial implementation loads only after the SDK's boot function runs in a WebSpatial runtime. A separate "eager" entry point was added for client-rendered apps that only target spatial platforms. The same release added an animation API for 3D entities, with native playback on visionOS through RealityKit.

Design

WebSpatial API

The proposed API extends existing web building blocks rather than replacing them. The documentation lists these main features:

Feature	Description
Spatial scenes	The start page of a web app (a PWA), and each page of the same app opened in a new window, becomes a spatial scene container integrated with the surrounding space.
Material backplates	A window's background can use a translucent material rendered from the viewpoint and environment, or be made fully transparent so elements appear to float.
Volumetric windows	A window can behave like a box with real volume and depth instead of a flat panel.
Spatialized HTML elements	Ordinary HTML elements can be moved along the Z axis in front of the page with CSS, rotated in 3D and given material backgrounds, while still taking part in CSS layout.
3D container elements	Static containers render prebuilt 3D model asset files through an API based on the HTML model element; dynamic containers render 3D content through an HTML-style 3D engine API.
2D attachments	2D HTML content can be attached to plane-shaped 3D entities inside 3D content.
Spatial interactions	Tap, drag, magnify and rotate events report positions and motion in 3D coordinates.

The documentation calls its development model "2D containing 3D": a project stays a normal 2D website, and 3D content is confined to local 3D spaces inside containers that join the 2D layout. It contrasts this with WebXR, which renders independently with low-level graphics APIs and puts all of an app's content in a single session. WebSpatial instead uses a declarative 3D engine API that the operating system can understand, so the system can render web content together with other apps in the same space. According to the project's concepts guide, apps built on OpenXR and low-level 3D graphics APIs, including WebXR content, are not "spatial apps" in this sense, because they render themselves and occupy the whole space exclusively. A WebSpatial app can still start a WebXR session, but its spatialized interface is hidden while the session runs.

SDK and packages

Because browser engines do not yet implement the proposed APIs, the SDK polyfills them inside the JSX, refs and CSS of React projects, together with a native runtime. The documentation states that the project's long-term aim is for the WebSpatial Runtime to be implemented inside browser engines. On platforms without spatial computing support the SDK ignores the WebSpatial APIs and skips loading its full implementation.

The repository README lists four npm packages:

Package	Role
@webspatial/react-sdk	React integration; installed through the JSX runtime setting (jsxImportSource) of a project
@webspatial/core-sdk	Underlying runtime-facing SDK
@webspatial/builder	Command-line tool (run, build, publish) that packages a site as a native app, previews it in a simulator and uploads it to App Store Connect
@webspatial/platform-visionos	visionOS runtime used by the Builder

The repository's code is mostly TypeScript, with a smaller share of Swift. The React SDK is the only framework integration offered so far; the build tools the project lists as tested most are Vite, Next.js, Remix, and Rspack, Rsbuild and Webpack. A site must also provide a Web App Manifest so that it meets the minimum requirements of a Progressive Web App.

Supported platforms

Platform	Status (October 2026)	How WebSpatial runs
visionOS (Apple Vision Pro)	Supported	The site is packaged with WebSpatial Builder as a hybrid app that contains the WebSpatial Runtime and renders pages through WKWebView. Safari on visionOS runs the same site as an ordinary web page.
PICO OS 6	Supported	The system Web App Runtime includes the WebSpatial Runtime, so a site works without packaging when run as a standalone web app. The default PICO browser runs it as an ordinary page.
JSAR Runtime (Rokid glasses), IRIS OS	Runtime in progress	Listed as working toward a WebSpatial Runtime implementation
Android XR, Meta Horizon OS	Planned	Listed as priority targets waiting for stable native APIs
Desktop and mobile browsers	Normal website	WebSpatial APIs are ignored and the site displays as usual

On visionOS, packaged apps cannot currently start a WebXR session, because WKWebView on visionOS does not support WebXR. For distribution, the Builder's publish command uploads a packaged app to App Store Connect for the visionOS App Store. The PICO store can list a web app by its URL, but as of October 2026 the documentation says PICO has no self-service web app submission, so such apps go through PICO's business partnership channels. Packaged visionOS apps are debugged with Safari Web Inspector on a Mac, and PICO OS 6 web apps with Chrome DevTools remote debugging.

Release history

Version	Date	Notes
React SDK 0.0.8	11 March 2025	Earliest release listed in the GitHub repository
Core SDK 0.0.2	19 March 2025	First listed Core SDK release
1.0.0	7 July 2025	First major version
2.0.0	21 August 2026	Lazy-loading default entry, separate eager entry, entity animation API

See also

• WebXR
• PICO OS
• VisionOS
• Meta Spatial SDK
• Unity PolySpatial