Support

Open the Chrome Web Store listing and click "Add to Chrome." The extension activates automatically when you visit reddit.com or old.reddit.com. No setup, no sign-in.

Refresh the Reddit tab once. Browser extensions only inject into pages loaded after install. If you still don't see the play button on posts, make sure ThreadCast is enabled in chrome://extensions and that you're on a thread page (not the subreddit feed).

Chrome 88+ and any Chromium-based browser (Edge, Brave, Arc, Vivaldi, Opera). Safari and Firefox are not supported; they use different extension systems.

System voices use the speech voices already on your device: instant, zero download, unlimited voices, quality varies by OS. AI neural CPU is a neural model running on WASM (~63 MB per voice, 5 hand-picked English voices). AI neural GPU runs on WebGPU (~325 MB once for 11 voices). All three run fully on your device, so you can switch from the popup at any time.

Click the engine card to start the one-time download. The progress bar shows per-file progress for the model, tokenizer, and 11 voice embeddings. After the download completes (~325 MB total) the engine runs offline forever. If the download fails, check that WebGPU is supported in your browser at chrome://gpu: look for "WebGPU: Hardware accelerated."

Some integrated GPUs and older drivers have known compatibility issues with the WebGPU runtime under heavy neural workloads. If you hit this, switch to AI neural CPU (also studio-grade, just slower) or System voices, both of which work on every device.

Yes. Open Settings → Author overrides, search for the username, and pin a voice. Overrides survive across threads and sessions. Useful for AMAs, recurring posters, or favorite mods.

We hash each unique username with FNV-1a and map it to a voice from your enabled set. The same username always gets the same voice across every thread. You can choose how many voices rotate (1–10 on System voices, up to 11 on AI neural GPU) and toggle individual voices on or off in Settings.

This was fixed in the latest update. If you still see it, check chrome://extensions, click "Update" on ThreadCast, then refresh the Reddit tab.

It shouldn't. Playback runs in a Chrome offscreen document and continues across tabs. If it stops, your browser may be aggressively suspending the offscreen document for memory. Try keeping the Reddit tab pinned or in the background instead of fully closing it.

Yes. Click and drag anywhere on the segment progress bar. The scrubber updates as the current segment plays, with no audio doubling on jumps.

Open the popup → Sleep mode toggle. Pick an ambient track, set a fade-out timer if you want one, and play any thread. Voices automatically slow to 0.85× and the ambient loop layers under the narration.

Yes. Sleep mode has independent sliders for voice volume and ambient volume, plus a separate sleep rate (default 0.85×). Tune them in Settings → Sleep mode.

On Chrome, yes, provided your OS allows background audio (Windows and macOS do by default). On Android, the app handles this natively via a foreground service and lock-screen controls.

Yes. All speech synthesis runs on your device, so no audio, no text, and no usage data ever leaves your browser. AI neural engines download their voices once, then run fully offline.

Locally on your device, plus optional sync via your own Chrome account (Chrome's built-in sync). We never see them. Use Settings → Import / export to back them up as a JSON file.

In Chrome DevTools (F12) on any tab, run caches.delete('transformers-cache') for GPU models or open the extension's storage section in chrome://extensions → ThreadCast → Storage. Or simply uninstall: Chrome wipes all extension storage on uninstall.

Yes, the Android app is live on Google Play now. Free to download, with Premium for on-device AI neural voices and MP3 export. Grab it from the home page, or email us.

After Android stabilises. Same feature parity, native iOS patterns (CarPlay, Shortcuts, lock-screen controls). Join the waitlist on the iOS page.

ThreadCast Premium is the paid tier on Android: it adds on-device AI neural voices and MP3 export on top of the free tier (System voices, sleep mode, queue, author-aware narration). iOS follows later with the same Premium tier. One subscription covers both the extension and mobile. The first 100 Lifetime purchases are $69 instead of $99. See Pricing for the full breakdown.