Show HN: On-Device TTS with Synchronized Text Highlighting in the Browser

We built a tool that lets you turn any public webpage into audio with synchronized text highlighting — directly in your browser.

No servers, no limits, no subscriptions. It’s free and works entirely on your device.

How it works: - Take any URL and add "with.audio/" to the beginning - Example: "with.audio/https://example.com/article" - Open it in your browser, wait for the paragraphs to load, then click play - The text-to-speech happens locally in your browser tab, with highlighting

The first time you try it, your browser will download a voice model (Kokoro ~300MB, Piper is lighter). After that, it works offline and almost instantly (depending on the device).

If you like to read a bit about how it works, take a look at this: https://blog.with.audio/posts/web-reader-tts

Note: we send the your URL to our backend to get the HTML content.

Would love your feedback — what works well for you, and what feels rough?