CastReader is a browser extension that reads web pages, Kindle Cloud Reader books, PDFs, and AI chatbot responses aloud in natural AI voices across 40+ languages, with real-time word highlighting and a unique Read & Explain mode that explains the text in plain language as it reads.
What is CastReader?
CastReader is a text-to-speech and reading comprehension tool available as a browser extension for Chrome, Edge, and Firefox, and as a mobile app for iPhone and iPad. It takes any web page, PDF, Kindle book, or AI conversation and outputs either a natural-voice narration with synchronized highlighting or an explanatory audio that paraphrases the content in simpler terms in the user's preferred language. The extension is developed by an independent team and is free to start with no login required.
Key Features
- Read & Explain (Quickread): When you encounter a dense or foreign-language passage, Quickread explains the meaning in the language you know while a moving pen circles, underlines, and highlights key points on the original page — bridging comprehension gaps without leaving the source.
- Kindle Cloud Reader support: CastReader is one of the few TTS tools that works on Kindle Cloud Reader. It reads DRM-protected Kindle books aloud chapter by chapter with auto page-turning, and can hand off audio to your phone via Telegram's Send to Phone feature.
- AI chatbot playback: A play button appears next to responses from ChatGPT, Claude, Gemini, DeepSeek, and other AI platforms, allowing you to listen to a single answer without copying text. Quickread also works on confusing AI explanations.
- Universal text selection: Highlight any text on any page, right-click, and select "Read Selected Text" to hear just that passage with paragraph highlighting. Over 40 languages auto-detected with native-sounding voices.
- Website reading mode: One-click extraction of article content (stripping ads, navigation, sidebars) with natural AI voices and word-by-word highlighting, ideal for long reads.
- Document and email integration: A listen button appears beside Google Doc titles, Gmail subjects, Notion pages, and more, enabling hands-free proofreading or listening to long threads.
- Send to Phone: Start listening on your computer, then tap to continue on your phone via Telegram — useful for taking a book or article on the go.
- Cross-language support: 40+ languages are supported for both reading aloud and explaining, with native voices for each.
Add to Chrome — the extension is free to install.
Who is it for?
- Students and researchers: Listen to textbooks, research papers, and lecture notes while commuting or exercising, absorbing material through dual-channel learning.
- Language learners: Hear proper pronunciation in any of 40+ languages while reading along, or have foreign articles explained in their native language.
- Professionals and executives: Catch up on industry reports, newsletters, and long-form analysis during the commute without screen fatigue.
- Dyslexia and ADHD readers: Audio paired with visual highlighting reduces reading fatigue and keeps focus, with adjustable speed and synchronized paragraph tracking.
What can you do with CastReader?
- Turn any webpage into a podcast: Click the extension icon on a news article, blog, or newsletter to listen to a clean, ad-free reading with natural AI voices and paragraph highlighting.
- Have a foreign language page explained: When reading a French, Chinese, or German article, enable Quickread to hear it explained in English (or your chosen language) while the key points are marked on the original.
- Listen to Kindle books as audiobooks: Open Kindle Cloud Reader, press play, and CastReader narrates chapter by chapter with auto-advance. Use Send to Phone to continue on your commute.
- Proofread by ear: In Google Docs or Gmail, click the listen button to have your draft read aloud, catching errors your eyes might miss.
- Get AI explanations narrated: After a complex ChatGPT answer about quantum entanglement or code, click the play button to listen, or run Quickread to unpack it in simpler terms.
Pricing
CastReader offers a Free tier with 20 minutes of listening per day, standard AI voices, and 3 explains per day. The Pro plan (approximately $3/month billed yearly) removes the daily cap, adds 100+ premium voices up to 3× speed, and includes unlimited explains. There is also a mobile app available on iPhone and iPad.
FAQ
Is CastReader free?
Yes, the Free tier is $0 forever and includes 20 minutes of listening per day, standard voices up to 2× speed, and 3 AI explains per day. No signup or login required.
Does it work on any website?
Yes, CastReader works on any website when you click the extension icon or right-click and select "Read Selected Text". It also has dedicated integrations for Kindle Cloud Reader, WeRead, O'Reilly, Google Docs, Gmail, Notion, ChatGPT, Claude, Gemini, and more.
How does it handle Kindle's DRM?
CastReader reads directly from the screen — it uses OCR to extract text from Kindle Cloud Reader pages, so it works with DRM-protected content. It also supports auto page-turning and Send to Phone.
Does it support languages other than English?
Yes, 40+ languages are supported for both reading aloud and Quickread explaining. Auto-detects language and picks a native-sounding voice.
Will it slow down my browser?
CastReader is lightweight and only activates when you click to read or explain. It does not run in the background unless you are actively using it.