Last updated: October 5, 2026
SpeakFit reads your text aloud entirely on your device. Your text is never uploaded, transmitted, or stored anywhere outside your browser. We collect no personal data.
All speech is made locally in your browser using JavaScript and WebAssembly. The text you paste or open, and the audio made from it, never leave your computer. Once the voices are downloaded, you can disconnect from the internet and SpeakFit keeps working. Your voice and speed choices are kept in your browser's local storage.
When you click SpeakFit's toolbar button, the extension reads the text of the page you are on — or only your selection — and hands it to SpeakFit's own page, through the browser's session storage (held in memory and cleared when the browser closes). It reads only that one tab, only when you click, and sends nothing anywhere. The right-click "Read aloud with SpeakFit" item works the same way with the text you selected.
SpeakFit uses the open Kokoro voice model. It needs a one-time download of the voices
(about 100 MB) from speakfit.mrrage.dev, and only fetches them when you press
Download the voices. The request asks for those files and sends nothing
about you or your text. Each file is checked against a fixed fingerprint (SHA-256) and
stored in your browser's own storage (Cache Storage). Delete the voices
removes them.
The SpeakFit browser extension collects nothing: no analytics, no telemetry, no cookies, no account, no ads. Its permissions are used only as described above: "activeTab" and "scripting" to read the page you click the button on, "contextMenus" for the right-click item, and "storage" to pass the text to SpeakFit's page and to remember your Pro license key.
Purchases are processed by Lemon Squeezy (their privacy policy applies to checkout). Keys bought through Lemon Squeezy are checked once, with Lemon Squeezy, when you enter them; that request contains only the key. Older bundle keys (they start with FIT1) are checked on your device, with no request. After that, the key is kept only in your browser's local storage and isn't checked again.
SpeakFit is free software under the GNU General Public License, version 3 or later — source code. It uses the Kokoro voice model and kokoro-js (Apache-2.0), eSpeak NG through phonemizer.js (GPL-3.0-or-later), transformers.js (Apache-2.0) and ONNX Runtime Web (MIT).