Spiel: Chrome extension that reads articles/PDFs aloud with local TTS

Spiel, a free and open-source Chrome extension, reads articles and PDFs aloud using a local neural voice model on Macs with Apple Silicon, ensuring privacy by processing everything on-device without cloud connectivity or data collection.

Listen to any article or PDF with a natural AI voice — free, private, and 100% local. An open-source alternative to Speechify — without the $139/year, and without your reading history flowing through someone else's servers. Read-aloud tools are either expensive subscriptions or cloud services that see everything you read. Spiel is neither: the neural voice Kokoro-82M https://huggingface.co/hexgrad/Kokoro-82M runs on your own Mac at 127.0.0.1 . No account, no telemetry, no cloud. Turn off Wi-Fi and it still works. Built for students, researchers, and anyone who reads a lot and wants to pay nothing. ▶️ One click to listen — open any article or PDF, press Play- 🖍 Word-by-word highlighting that follows the voice, with auto-scroll - 📄 Reads PDFs — research papers, web-hosted or local, extracted on-device with pdf.js - 👆 Click anywhere to listen from there — click a paragraph, reading jumps to it - ✂️ Read your selection — select text on any page for instant playback - 🎚 4 curated voices American/British, male/female and speed up to 3× - ⏱ Time-remaining estimate at your current speed - 🧹 Smart skipping — URLs, reference brackets , parentheses — your choice - 🌙 Dark mode everywhere, matched to the page - 🔒 100% local — text-to-speech happens at 127.0.0.1 ; nothing ever leaves your machine Requirements: Mac with Apple Silicon M1 or newer · ~8 GB free disk · Chrome. Intel Macs and Windows/Linux: on the roadmap. ⬇ Download the latest spiel-extension.zip , unzip it, then: - Open chrome://extensions - Toggle Developer mode ON top-right - Click Load unpacked and pick the unzipped folder - Pin the 🎙 Spiel icon to your toolbar Keep the folder somewhere permanent not Downloads — Chrome loads the extension from that exact path. A one-click Chrome Web Store install is coming. Or build from source git clone https://github.com/preet01/spiel.git cd spiel && npm install && npm run build Then Load unpacked → pick the dist/ folder. Paste this in the Terminal app and press Enter: curl -fsSL https://raw.githubusercontent.com/preet01/spiel/main/install.sh | bash Wait ~2 minutes. When your Mac says "Spiel is ready" out loud, you're done — open any article and press Play in the Spiel popup. What does that command install, exactly? Everything goes under ~/.spiel plus one LaunchAgent . The script: - Checks your Mac macOS, disk space - Installs the uv https://github.com/astral-sh/uv Python manager if missing - Downloads Kokoro-FastAPI https://github.com/remsky/Kokoro-FastAPI pinned commit, Apache-2.0 - Downloads the Kokoro voice model ~330 MB, Apache-2.0 - Creates a LaunchAgent so the engine auto-starts on boot, bound to 127.0.0.1 only — unreachable from the network - Starts it and speaks a test sentence It's ~300 lines of plain bash — read it yourself /preet01/spiel/blob/main/install.sh before running, as you should with any curl | bash . ┌────────────────────────── Your Mac ──────────────────────────┐ │ │ │ Chrome Kokoro voice engine │ │ ┌──────────────────┐ text ┌───────────────────────┐ │ │ │ Spiel extension │ ───────▶ │ FastAPI + Kokoro-82M │ │ │ │ UI, highlights │ ◀─────── │ at 127.0.0.1:8880 │ │ │ └──────────────────┘ audio └───────────────────────┘ │ │ │ └────────────── nothing crosses this line ─────────────────────┘ The extension extracts the article Readability https://github.com/mozilla/readability or PDF pdf.js https://mozilla.github.io/pdf.js/ , on-device , sends it sentence-by-sentence to the local engine, and plays the audio with synchronized word highlighting driven by Kokoro's word timestamps. - No analytics, no telemetry, no accounts, no remote servers. - The voice engine listens on 127.0.0.1 only — your own machine, not your network. - The only network traffic Spiel ever creates is the one-time download of the engine and model at install. | Problem | Fix | |---|---| | Popup says "Voice not installed" | Run the Step 2 command; the popup updates itself when the engine is up | | Installed but silent | Engine log: ~/Library/Logs/spiel-voice-engine.log · installer log: ~/.spiel/install.log | | Local PDF won't read | Enable Allow access to file URLs for Spiel at chrome://extensions | | Port 8880 already in use | Another app owns it — lsof -iTCP:8880 -sTCP:LISTEN to find it | | First play of the day is slow | The model warms up on first request ~5–15 s ; Spiel keeps it warm afterwards | | Uninstall everything | curl -fsSL https://raw.githubusercontent.com/preet01/spiel/main/uninstall.sh | bash + remove the extension at chrome://extensions | Issues and PRs welcome — especially Intel Mac / Windows / Linux ports , new voices, and Firefox support. The codebase is small and documented: | File | What it does | |---|---| src/background.ts | Playback state machine, TTS fetches, prefetch cache | src/content.ts | Article extraction, word highlighting, floating player | src/offscreen.ts | Audio playback Web Audio, autoplay-exempt | src/pdf-content.ts | On-device PDF text extraction pdf.js | The build has two quality gates: a strict TypeScript check and a dist-completeness check that fails if any runtime file is missing. Before contributing, read LESSONS.md /preet01/spiel/blob/main/LESSONS.md — every past bug, its root cause, and the pre-flight checklist that keeps them from coming back. npm run build typecheck → bundle → icons → verify dist/ completeness npm run package dist/ → spiel-extension.zip - True one-click: run the voice inside Chrome via WebGPU no Terminal step at all - Chrome Web Store listing - In-PDF page highlighting Spiel Reader view - Windows & Linux installers - More voices and languages - Firefox support MIT /preet01/spiel/blob/main/LICENSE © Harpreet Vishnoi. Built on excellent open-source work — see THIRD PARTY.md /preet01/spiel/blob/main/docs/THIRD PARTY.md for full credits Kokoro model & Kokoro-FastAPI, Apache-2.0; Mozilla Readability, Apache-2.0; pdf.js, Apache-2.0; and the CC BY voice datasets behind Kokoro . Spiel is not affiliated with, endorsed by, or connected to Speechify Inc. in any way.