CastReader reads textbooks, research papers, lecture notes, and articles aloud with paragraph highlighting. Study while walking, commuting, or cooking. Free Chrome extension — no signup needed.
Turn reading assignments into listening sessions
Open your textbook on Kindle Cloud Reader (read.amazon.com) and click CastReader. It's the only Chrome extension that works on Kindle — every other TTS extension fails because Amazon encrypts the text. CastReader uses OCR to read what's on screen. Your entire Kindle library becomes listenable.
ArXiv, Google Scholar, PubMed, SSRN — CastReader reads papers from any source. It extracts the article content and skips headers, footers, and reference lists. Highlight tracking keeps your place while the paper is read aloud. Great for first-pass reading before deep analysis.
Listen to assigned readings while walking to class, working out, or doing laundry. CastReader's Send to Phone feature streams audio to your phone via Telegram — start reading on your laptop, continue listening on your phone. Turn dead time into study time.
Dual-channel learning — hearing text while seeing it highlighted — improves retention compared to reading alone. CastReader highlights each paragraph as it's read, so you get both visual and auditory input simultaneously. Speed it up for review, slow it down for new material.
Lecture notes in Google Docs. Assigned PDFs. Wikipedia deep dives. ChatGPT explanations. CastReader reads them all with the same one-click experience. No need to copy-paste text into a separate app.
The average college student is assigned 200-400 pages of reading per week. That's across 4-5 classes, each with textbooks, journal articles, and supplementary materials. Nobody actually reads all of it. Students skim, skip, and cram — not because they're lazy, but because there aren't enough hours to read everything carefully while also attending lectures, writing papers, and maintaining basic human functions like sleeping.
Text-to-speech changes the math. When you can listen to readings while walking between classes, doing laundry, or commuting, those dead time slots become study time. A 30-minute bus ride turns into a chapter of your sociology textbook. A 20-minute walk becomes an arXiv paper for your ML class. You're not replacing careful reading — you're adding a first-pass that primes your brain for deeper engagement when you do sit down to study.
CastReader is designed for this workflow. It reads any webpage — textbooks on Kindle Cloud Reader, papers on Google Scholar, notes on Google Docs — with paragraph highlighting so you can follow along visually or just listen. Speed control lets you go faster on familiar material and slower on dense passages. It's free to use — no signup — which matters when you're a student, and you can upgrade to CastReader Pro for premium voices, more listening hours, and AI document analysis when you need them.
The technical challenge is that many academic sources use unusual page structures. Kindle encrypts text with custom fonts. arXiv papers are rendered as static images. Google Docs uses a complex internal editor. CastReader has dedicated extractors for all of these — it understands each platform's specific DOM structure instead of trying to read random text from the page.
Common questions about using text to speech for studying
Yes, CastReader is free to use for everyone — no student email required, no verification, no signup. The free tier covers everyday studying with natural AI voices; upgrade to CastReader Pro for premium voices, more listening hours, and AI document analysis. Install from the Chrome Web Store and start using it immediately.
Yes. Open your textbook on Kindle Cloud Reader (read.amazon.com) and click CastReader. It's the only Chrome extension that works on Kindle because it uses OCR to bypass Amazon's encrypted fonts. Every other TTS extension fails on Kindle.
Research shows that combining audio with visual text improves comprehension and retention compared to reading alone. TTS is especially effective for first-pass reading — it primes your brain for deeper engagement when you review later. It also lets you study during time you'd otherwise waste (commuting, walking, exercising).
Yes. CastReader's Send to Phone feature streams audio to your phone via Telegram. Start reading on your laptop, grab your phone, and the audio continues as you walk. It even auto-turns pages for Kindle books.
Yes. CastReader has dedicated extractors for Google Docs, PDFs viewed in the browser, Notion, and many other platforms. It reads the document content and skips UI elements. One click, same experience everywhere.
Yes. CastReader reads papers from arXiv, Google Scholar, PubMed, and any academic publisher's website. It extracts the paper content and skips headers, navigation, and reference formatting. Great for getting through reading lists faster.
Speed control goes from 0.5x to 3x. Most students use 1.5x-2x for general reading and slow down for technical or unfamiliar material. You can adjust the speed while listening without any interruption.
No. Text to speech is a reading tool, not a writing tool. It's officially recognized as an accommodation by most universities and standardized testing organizations. Using TTS is no different from listening to an audiobook version of your textbook.
Download the CastReader app to listen to your uploaded documents anywhere.
Hard numbers — not vibes — from authoritative sources
$2.22 billion
US audiobook sales in 2024, up 13% year-over-year (Publishers Weekly / Audio Publishers Association)
Source →51%
of US adults have listened to an audiobook in 2025 — roughly 134 million people (APA Consumer Survey 2025)
Source →2.2 billion
people globally with near- or far-vision impairment (WHO Fact Sheet, 2024). TTS is the primary access path for digital reading content.
Source →78%
of audiobook listeners multitask while listening — commute, chores, exercise (Audiolibrix Great Audiobook Survey, 2024)
Source →27.2 minutes
average single-trip US commute in 2024, up from 26.8 (US Census ACS via Statista). That's nearly an hour each day of audio-only time.
Source →effect size 0.35
measured comprehension lift from TTS for reading-disabled students across 22 studies (Wood, Moxley, Tighe & Wagner, Journal of Learning Disabilities, 2018)
Source →15.5 million
US adults with ADHD per CDC 2024 — about half diagnosed in adulthood (CDC MMWR, October 2024)
Source →Every Chrome Web Store review below is verifiable at the link in each card. We don't hide negative feedback — we answer it within 24 hours.
“This is 1 of the best TTS and its smooth. If this is truly free i'll keep this 100%. Every other TTS says its free but has a secret. They interrupt or they just say better ai voices pay. But i like this voice. I've tried loads and this is 1 of the best ones that actually says free.”
“Works perfectly on vivaldi. One suggestion though. I wish it had a play button appear next to a paragraph when we hover over it. Just like in the case of speechify.”
“Extremely user friendly short keys. Placed forward backward and speed up down as Natural as it could be. Voices are great and smooth. I would recommend it over many hyped products.”
“At the very least it's better than many paid TTS models. Still not as good as ElevenReader or LAP, but maybe the best free model for TTS.”
“So glad I can finally switch voices! The default was fine but I found one I actually enjoy listening to for hours. Small thing, huge difference.”
“Best one i found, user friendly, and great voice over.”
“ChatGPT's long answers are finally listenable. Let it generate while I listen — doubles my productivity. Love the inline button next to each response.”
“I tried using this add-on to listen to an ebook on the O'Reilly learning platform, and it works smoothly. However, it always restarts from the first paragraph whenever I scroll or select a different paragraph. Please consider adding a bookmark or checkpoint feature so users can mark where the reading should begin.”
↪ Founder reply
Replied by CastReader founder Yan Xu within 48 hours: acknowledged the issue, shipped a bookmark feature in the following release. Reviewer's verbatim feedback drove the v1.2 roadmap.
“Need to highlight text and select it.”
“Hard to select text.”
↪ Founder reply
Replied by CastReader founder Yan Xu within 24 hours: apologized, asked which site/browser the issue occurred on, provided a workaround using the keyboard shortcut, and offered direct support at support@castreader.ai.
We re-test, re-write, and ship continuously. Every entry has a real date.
Rewrote landing pages with verbatim Chrome Web Store testimonials, real audiobook market data, and tested-12-extensions methodology. Every claim now has a sourceable link.
Telegram audio streaming now auto-turns pages reliably across Kindle Cloud Reader and Apple Books. Reduces session interruptions by ~70% in internal testing.
Wrote up the OCR pipeline: how CastReader handles Amazon's 184 random font alphabets and 361 unique glyphs per Kindle book. Shared in dev.to.
Native macOS app reads Kindle for Mac with word-level highlighting. Floating player + system-wide hotkeys. No browser needed.
Ranked #10 in Daily, 99 upvotes, 4 community comments shaped the v1.2 roadmap.
Switched from older TTS engines to Kokoro neural voices. User reviews shifted from 'usable but robotic' to 'enjoy listening for hours' (verbatim from review by patrick chiang).
OCR success rate improved from 78% to 89% on English-language Kindle books. Multi-column page detection added for academic PDFs.
I built CastReader because I owned hundreds of Kindle books and couldn't listen to them on my morning runs without buying separate Audible copies. The technical problem — Amazon's Cloud Reader font encryption — turned out to be solvable with OCR. The product problem — making it actually pleasant across phones, desktops, and 40+ languages — took two years of iteration. We're a small team. I answer every Chrome Web Store review personally (see testimonials above — including the 3-star and 1-star ones). If something's broken or missing, email support@castreader.ai.
— Yan Xu, founder
Last reviewed: · CastReader Team — reviewed against 2025 testing data
Free to use. No signup. Install and start listening — upgrade to CastReader Pro for premium voices, more listening hours, and AI document analysis.
★★★★★ 4.7 · Free to start · No login · Optional Pro