CastReader — Free AI Text to Speech Reader Firefox

CastReader — Free AI Text to Speech Reader

By: Vin Xu
Read aloud any webpage, PDF, or Kindle book with natural AI voices. Free text-to-speech with real-time highlighting. 40+ languages.
CastReader — Free AI Text to Speech Reader
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Features & Capabilities

CastReader — Free AI Text to Speech Reader

Short Description (132 chars max)

Read aloud any webpage, PDF, or Kindle book with natural AI voices. Free text-to-speech with real-time highlighting. 40+ languages.

Detailed Description

CastReader is a free AI text-to-speech extension — read aloud any webpage, PDF, or Kindle book with natural AI voices. Follow along with real-time paragraph highlighting as you listen. No signup, no limits, completely free forever.

Free Text to Speech Extension — Why CastReader?

Unlike built-in browser TTS or basic read aloud extensions, CastReader uses Kokoro — an advanced AI voice engine that sounds genuinely human. It intelligently extracts the main article content, skipping menus, ads, and sidebars. One click to read any page aloud. The only text-to-speech Chrome extension that works on Kindle Cloud Reader.

Key Features

  • 🔊 Read aloud any webpage with one click — articles, blogs, docs, PDFs
  • 🎯 Real-time word and paragraph highlight tracking as you listen
  • 🗣️ Natural-sounding AI voices powered by Kokoro TTS engine
  • 🧠 Smart content extraction — automatically finds the main text
  • 📖 Special support for Kindle Cloud Reader and WeRead (微信读书)
  • 📱 Send to Phone — continue listening on your mobile
  • ⚡ Adjustable playback speed (0.5x to 2x)
  • 🌐 40+ languages with automatic language detection
  • 💰 100% free — no signup, no limits, no premium tier
Read Aloud Any Website

Works everywhere including:

  • News and blogs: Medium, Substack, Reddit, Hacker News
  • Research papers: arXiv, Google Scholar, PubMed
  • Online documents: Notion, Google Docs, Confluence
  • E-readers: Kindle Cloud Reader, WeRead (微信读书)
  • AI assistants: ChatGPT, Claude, Gemini, DeepSeek
  • Social media: Reddit, Twitter/X, Zhihu

Perfect For

  • Listening to articles while commuting or exercising
  • Students who learn better by listening
  • People with dyslexia, ADHD, or visual impairments
  • Proofreading your own writing by hearing it read back
  • Language learners practicing listening and pronunciation
  • Accessibility — screen reader alternative with highlight tracking
  • Anyone who prefers audiobooks over reading
40+ Languages Supported

English, Chinese, Japanese, Korean, French, German, Spanish, Portuguese, Russian, Arabic, Hindi, Turkish, Vietnamese, Italian, Dutch, Polish, Thai, Indonesian, and 25+ more. Language is automatically detected — no setup needed.

How to Use

  1. Navigate to any webpage
  2. Click the CastReader icon in the toolbar
  3. Press "Read This Page"
  4. Listen and follow along with the highlighted text
100% Free — No Limits, No Subscription

CastReader is completely free with no usage limits. Natural AI voices, real-time highlight tracking, Kindle Cloud Reader support, and send-to-phone — all included at no cost. No monthly limits, no premium upsell, no account required.

Privacy First

CastReader only processes text when you click "Read This Page". No data is collected or stored. Audio is generated on-the-fly and not cached. Open source on GitHub.

User Growth & Download Statistics

Manifest V3 Add-on
By:
Vin Xu
Daily users:
95 16
Rating:
4.00
(1)
Version:
1.0.2 Last updated: 2026-03-19
Version code:
6183472
Creation date:
2026-03-16
Risk:
High risk impact Moderate risk likelihood
Permissions:
Host permissions:
  • *://api.castreader.ai/*
  • *://castreader.ai/*
  • *://weread.qq.com/*
  • *://read.amazon.com/*
  • *://read.amazon.cn/*
  • http://localhost:18789/*
  • http://localhost:18790/*
Content scripts matches:
  • read.amazon.cn
  • read.amazon.com
  • weread.qq.com
Size:
3.55MB
Email:
su*****@castreader.ai
URLs:
Website
Full description:
See detailed description
Source:
Firefox Add-ons Store
Data ingested on:
2026-06-03
Compare stats and ranking:

Ranking

# 11,394 ▲ 1,019
Other rankings
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Other platforms

Chrome
CastReader — Free Read Aloud for Kindle, Articles, PDFs · TTS + Highlight (v1.1.9)
2,000 4.70 (30)

For Developers

Monetize with App Pass Boost with Extension Booster

Contact the developer

Chrome-Stats does not own this Firefox add-on. Please use these information below to contact the Firefox add-on developer.
Developed by:
Vin Xu
Firefox Add-ons Store
https://addons.mozilla.org/firefox/addon/castreader-tts-reader/
Email:
su*****@castreader.ai
Website:
https://castreader.ai/

User Reviews

"Error: TTS generation failed for first paragraph: NetworkError when attempting to fetch resource." This is all I get. I'm leaving this at 4* for now as the project is a good one and I don't want to crash it with a first Review, but I'll be back, and for the moment, it doesn't work.
by Ne*****, 2026-06-01
View all user reviews ›

Is CastReader — Free AI Text to Speech Reader Safe?

Risk impact
Risk impact measures the level of extra permissions an extension has access to. A low risk impact extension cannot do much harms, whereas a high risk impact extension can do a lot of damage like stealing your password, bypassing your security settings, and accessing your personal data. High risk impact extensions are not necessarily malicious. However, if they do turn malicious, they can be very harmful.

CastReader — Free AI Text to Speech Reader requires some sensitive permissions that could impact your browser and data security. Exercise caution before installing.

Risk impact analysis details
  • Critical Request access to the following domains: amazon.cn, amazon.com, qq.com, castreader.ai, localhost
  • High ******* ******* **** *** ****** ***** *** ***** ** ******* **** ********* ********* ** * *********** *****
Risk likelihood
Risk likelihood measures the probability that a Firefox add-on may turn malicious. This is determined by the publisher and the Firefox add-on reputation on Firefox Add-ons Store, the amount of time the Firefox add-on has been around, and other signals about the Firefox add-on. Our algorithms are not perfect, and are subject to change as we discover new ways to detect malicious extensions. We recommend that you always exercise caution when installing a Firefox add-on.

CastReader — Free AI Text to Speech Reader is recently added, and hasn't been around long enough for us to gather enough data to accurately assess its risk level.

Risk likelihood analysis details
  • High This extension has low user count. Unpopular extensions may not be stable or safe.
  • Medium **** ********* *** ******* ** *** **** * ******* *** ******* *** *** ** ****** ** *****
  • Medium **** ********* *** ***** ** *** **** * ******* *** ********** *** *** ** ****** ** *****
  • Good **** ********* *** **** **** *******
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