CastReaderReview: reads pages and books aloud
CastReader reads web pages, PDFs, Google Docs and Kindle books out loud, highlighting each word as it goes and scrolling for you. It's a Chrome and Edge extension, with apps for iPhone and Android. When a passage gets dense, Read & Explain adds notes to the page and talks you through it, so you keep the original text instead of getting a summary. It recognizes nine languages on its own. You can start free without signing up: 20 minutes of reading and three explanations a day. Kindle is where it beats everyone else. Amazon's web reader scrambles its fonts, so extensions like Speechify, NaturalReader and Read Aloud end up reading gibberish. CastReader runs OCR in your browser on what's actually on screen, gets the words back, highlights them as it reads and turns the pages itself. It doesn't download or decrypt your books. It only reads what you're already looking at.
Keywords
text-to-speech, kindle, read-aloud, ocr, browser-extension
- Works on Kindle Cloud Reader: local tesseract OCR reads the rendered page, bypassing the font scrambling that breaks every mainstream TTS extension.
- Word-synced highlighting with auto-scroll: follow the text as it speaks, click a paragraph to jump there, auto-advance chapter by chapter.
- Read & Explain on the original page: difficult passages get annotated in place, in your language, with pointers back to the source text.
- Free to try without an account: 20 minutes of read-aloud and 3 explains per day; site-specific extractors for Notion, Google Docs, arXiv, Substack, ChatGPT, and more.
TMRW VERDICT
The read-aloud that survives Kindle's font scrambling
by TMRW Team·Oct 4, 2026
Read-aloud extensions are a crowded and mostly interchangeable bunch, and we wouldn't list another one without a good reason. CastReader's reason is Kindle. It works in Kindle Cloud Reader, where the big names fail, and it explains how: it runs OCR on the page as it's displayed and tracks where each word sits. Most tools in this category just say "AI". This one can tell you how its one hard trick works.
There are limits, and the site is upfront about them. It depends on how Cloud Reader currently lays out pages, publishers control some text-to-speech permissions, and the OCR only reads what's on screen in your own signed-in account. If you're cautious about Amazon's terms of service, read CastReader's FAQ before a long session. It's also not an audiobook. A narrator's performance and a synthetic voice reading OCR text are different things.
If you only want articles read aloud, you don't need it. Edge has a built-in reader and every competitor handles normal web pages fine. Install this one for a Kindle library you want to hear on your laptop or phone, or for Read & Explain when you're working through dense material in a second language. Its German support is especially thorough, covering voices, the interface and Kindle OCR.
Everything depends on whether the OCR and automatic page turns hold up over an hour of listening. The free tier needs no account, so try a chapter from your own library before you pay for anything.
