PortableWeb is an open file format for self-contained, sandboxed, interactive documents. Like PDF, but interactive. Like a webpage, but a file you own.
What it is
A PortableWeb bundle (.pweb) packages HTML, CSS, JavaScript,
and media into one file. A compatible viewer opens it in its own window,
sandboxed from the host system, with no network access by default.
The format is designed so that the document is the unit. You can save it, copy it, email it, archive it, or send it across an office network with AirDrop. It works offline. It doesn't expire when a CDN goes dark. It doesn't need a server. It doesn't need a subscription.
Each spec version freezes a stable subset of web platform features, so a bundle built against v1.0 will render correctly in any v1.0-compatible viewer, forever — the same archival promise PDF/A makes for static documents, applied to interactive ones.
Anatomy of a bundle
You can rename any .pweb file to .zip and unpack
it with any tool. There is no proprietary container, no hidden state, no
DRM. The format's strength is in its simplicity and its discipline, not in
its complexity.
application/vnd.portableweb+zip.
Design principles
A bundle carries everything it needs. No CDN dependency. No broken script tags in five years. No surprise network calls. Bundles are the unit of preservation.
No filesystem access, no surveillance APIs, network off by default. Storage scoped per bundle. Permissions declared upfront in the manifest, enforced by the viewer.
Each spec version freezes a stable subset of web features. A v1.0 bundle renders identically in any v1.0 viewer, indefinitely. New features ship in v2.0; old bundles don't break.
A bundle is a file. No host, no account, no subscription, no platform. You can copy it, archive it, mail it, or seal it in a time capsule. It belongs to whoever holds it.
What it's for
Slide decks with real interactivity, sent as a file. The natural successor to PDF for anything more than text.
A real home for the millions of interactive things that AI tools create. Stop deploying ephemera; start saving artifacts.
Interactive lessons that work offline, without a server, on any device — and still work next year, and the year after.
Journals, calculators, planners, trackers. Tools you keep as files instead of renting as subscriptions.
Reproducible figures, interactive supplements, simulations that stay reproducible across decades.
For libraries, museums, journals, and individuals who need interactive content to survive past the lifespan of any host.
How it differs
| Format | Interactive? | Offline? | Self-contained? | Archival promise? |
|---|---|---|---|---|
Limited |
Yes |
Yes |
PDF/A |
|
| Webpage / URL | Yes |
No |
No |
Link rot |
| PWA | Yes |
After install |
No |
No |
| EPUB | Partial |
Yes |
Yes |
For books |
| .pweb | Yes, fully |
Always |
Yes |
By design |
Roadmap
The ZIP layout, the mimetype convention, the manifest schema, the first example bundle. Specs and the hello.pweb bundle are public on GitHub.
Formal sandbox spec. The frozen subset of HTML/CSS/JS allowed in v1.0 bundles. First reference viewer (cross-platform).
CLI validator, mobile viewers, AI tool integrations. Specs evolve based on what people actually build.
From v1.0 forward, bundles render correctly in any v1.0-compatible viewer, forever. New features ship in v1.x and v2.x without breaking old bundles.
Get involved
PortableWeb is a small project with large ambitions. If any of this matters to you — as an engineer, an educator, an archivist, a designer, a researcher, a writer — there's a place for you in it.