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Preview of CastReader — Read Aloud + AI Explain

CastReader — Read Aloud + AI Explain by CastReader

Read with synced highlights and auto-scroll. AI explains difficult passages on the page. Natural voices in 28 languages.

Some features may require paymentSome features may require payment
3.3 (3 reviews)3.3 (3 reviews)
264 Users264 Users
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Extension Metadata

Screenshots
Read a Kindle book aloud with synchronized word highlighting and automatic scrolling.Explore a Kindle book with AI explanations and handwritten marks on the original page.Preview natural voices, see their portraits and save favorites across 28 languages.Open PDF and EPUB files and follow the original text with synchronized reading.Select the intended article or let Fix Agent repair the reading selection.
About this extension
CastReader helps you concentrate on long articles and documents. Natural text-to-speech, synchronized highlighting and automatic scrolling keep your eyes and ears on the same passage. Follow the original text without losing your place.

When a section is difficult, use AI Explain. It marks important passages on the page and guides you through the ideas while keeping the source visible.

What you can do
  • Read webpages, PDFs and EPUB books aloud.
  • Follow word and paragraph highlights as the audio plays.
  • Get explanations alongside the original content.
  • Extract the main article and click a paragraph to start there.
  • Adjust the speed, preview voices and choose your favorites.
  • View documents in their original layout.

28 reading languages

The interface and reading tools support 28 languages. Content language is detected automatically and can be corrected; the explanation language can be set separately. Voice availability varies by language. If a language has one standard voice, that voice is free; other languages offer free choices and additional Pro voices where available. Cloned voices have their own language limits. Arabic and Hebrew highlights follow right-to-left text.

Kindle Web compatibility depends on the book edition. Scanned documents require supported OCR and clear source images; OCR coverage differs from reading-language coverage.

Free and Pro

Start with 20 minutes of reading and 3 AI explanations per day for free. Pro provides unlimited reading and explanations, faster playback and more voices.

Privacy

Text is processed when you request reading or explanation. Anonymous product analytics exclude page text, document content, browsing history, file names and personal information.

Get started
  1. Open an article, a compatible Kindle book or a local document.
  2. Click CastReader or the headphone button.
  3. Choose Read Aloud or Explain.
  4. Listen while following the highlighted text.
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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
1.2.55
Size
44.95 MB
Last updated
a day ago (Oct 10, 2026)
Related Categories
  • Feeds, News & Blogging
  • Language Support
License
All Rights Reserved
Version History
  • See all versions
Tags
  • google
  • reddit
  • scholar
  • social media
  • twitter
  • youtube
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