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Preview of CastReader — Read Aloud + AI Explain

CastReader — Read Aloud + AI Explain by CastReader

Read Kindle, PDFs, articles and books aloud with synced highlights. AI explains difficult passages. Natural voices in 8 languages.

2.5 (2 reviews)2.5 (2 reviews)
202 Users202 Users
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About this extension
CastReader helps you stay focused on long content by combining natural text-to-speech, synchronized highlighting, and automatic scrolling. Listen and follow the text at the same time, without losing your place.

Use AI Explain when a passage is difficult. CastReader marks up the original page and walks you through the important ideas without replacing the source text.

What you can do
  • Read webpages, articles, PDFs, Word files, text files, and Kindle Cloud Reader aloud
  • Follow synchronized word and paragraph highlights while listening
  • Ask AI to explain difficult sections on the original page
  • Automatically extract the main content while skipping navigation and ads
  • Click a paragraph to continue from that position
  • Adjust playback speed and choose available voices
  • Use the document reader without changing the original layout

8 supported reading languages

English, Mandarin Chinese, Japanese, Spanish, French, Brazilian Portuguese, Italian, and Hindi. CastReader detects the content language automatically. English and Chinese include expanded voice choices; the other supported languages use an automatically selected matching voice.

Free and Pro

Start free with 20 minutes of read-aloud and 3 AI Explains each day. Pro unlocks unlimited listening, unlimited Explain, faster playback, and more premium voices.

Privacy

CastReader processes text only when you ask it to read or explain. Anonymous product analytics never includes page text, document content, browsing history, file names, or personal information. Audio is generated on demand.

How to start
  1. Open a webpage, Kindle book, or document.
  2. Click CastReader or the headphone button on the page.
  3. Choose Read Aloud or Explain.
  4. Listen while the original text stays highlighted in sync.
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Permissions and data

Required permissions:

  • Access your data for all websites

Required data collection, according to the developer:

  • Browsing activity
  • Personal communications
  • Personally identifying information
  • Website content

Optional data collection, according to the developer:

  • Technical and interaction data
Learn more
More information
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Version
1.2.16
Size
4.62 MB
Last updated
5 hours ago (Jul 15, 2026)
Related Categories
  • Feeds, News & Blogging
  • Language Support
License
All Rights Reserved
Version History
  • See all versions
Tags
  • download
  • google
  • mp3
  • privacy
  • reddit
  • scholar
  • social media
  • translate
  • twitter
  • youtube
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