Webpage to ePub

A browser extension for Chrome and Firefox that converts the page you're reading into an ePub file — entirely in your browser.

Features

• Turns the current web page into a downloadable .epub;
• 100% client-side — the page is converted locally and nothing is uploaded to a server;
• Two ways to trigger: the toolbar popup button or the "Save page as ePub" right-click menu entry;
• Live progress, and conversion keeps running even if you close the popup;
• Manifest V3, works on both Chrome and Firefox from a single codebase.

Privacy

Everything runs in your browser. The page content is read from the open tab's live DOM and converted on-device — no page text, URL, or file is sent anywhere. Images embedded in the ePub are fetched directly from their origin so they can be packaged into the file; that is the only network access the extension makes.

Install

• Chrome Web Store
• Firefox Browser Add-ons

You can also build it yourself and load it unpacked (see below).

Build from source

Requirements: Node.js and npm.

npm install
npm run build          # produces dist/chrome and dist/firefox

Build a single target with npm run build:chrome or npm run build:firefox.

Load the unpacked build

Chrome (111+)

1. Open chrome://extensions.
2. Enable Developer mode.
3. Click Load unpacked and select dist/chrome.

Firefox (115+)

1. Open about:debugging#/runtime/this-firefox.
2. Click Load Temporary Add-on… and select any file inside dist/firefox (e.g. manifest.json).

Permissions

Permission	Why it's needed
host_permissions: <all_urls>	Fetch images referenced by the page so they can be embedded in the ePub.
scripting	Read the active tab's DOM on demand to capture the page content.
downloads	Save the generated ePub to your Downloads folder.
contextMenus	Add the "Save page as ePub" right-click entry.
offscreen (Chrome)	Run the converter in a hidden DOM document (the MV3 service worker has no DOM).

Development

npm run typecheck      # tsc --noEmit
npm run lint           # ESLint over src, tests, scripts
npm run format         # Prettier
npm test               # Playwright (Chromium) + Firefox via geckodriver

The conversion is powered by html2epub, a sibling project bundled into the extension at build time (never fetched at runtime). Because html2epub needs DOM globals, the background context differs per browser: Chrome uses an offscreen document, Firefox uses its DOM-capable background page.

For the full architecture, build pipeline, and testing notes, see CLAUDE.md.

License

MIT © Carlson Santana Cruz