CastReader adds text-to-speech to O'Reilly Learning Platform. Click play on any chapter — it reads aloud with paragraph highlighting, skips code blocks, and auto-advances to the next chapter.
Built for technical content — not just another generic TTS tool
O'Reilly has the world's largest technical book library — over 50,000 titles on programming, AI, DevOps, data science, and more. But fewer than 1% have audiobook versions. O'Reilly's mobile app has basic device TTS, but with robotic voices and no smart content filtering. Technical books deserve better.
Technical books are full of code snippets, tables, and diagrams that make no sense when read aloud. CastReader intelligently extracts only the readable text — paragraphs, headings, and list items — while skipping code blocks, tables, figures, and footnotes.
Each paragraph highlights as it's read aloud. Click any paragraph to jump there. The page auto-scrolls to follow the reading — so you can read along or just listen.
Scrolled halfway through a chapter? CastReader detects your reading position and starts from there — no need to listen from the beginning. Works on any page with URL anchors.
Free to use. No signup needed. Every book in your O'Reilly library becomes listenable — you're already paying for the O'Reilly subscription, so just install and listen. Upgrade to CastReader Pro for premium voices and more listening hours.
O'Reilly Learning (formerly Safari Books Online) is the gold standard for technical education — over 50,000 books from O'Reilly, Addison-Wesley, Pragmatic Bookshelf, Packt, and Manning, plus thousands of hours of video courses. If you're a software engineer, data scientist, or tech professional, chances are your company or university provides an O'Reilly subscription. The problem: almost none of these books have audiobook versions.
This matters because technical professionals are busy. You want to absorb 'Designing Data-Intensive Applications' during your commute, review 'AI Engineering' while cooking, or catch up on the latest Kubernetes book at the gym. But the only way to consume O'Reilly content is to sit down and read — until now.
O'Reilly's mobile app includes a basic read-aloud feature that uses your device's built-in TTS engine. It works, but the voice quality is robotic, it reads everything on the page (including code blocks, table headers, and figure captions), and there's no smart content filtering. For a 400-page technical book full of code examples, this is unusable.
CastReader solves this by adding intelligent text-to-speech to O'Reilly's web reader at learning.oreilly.com. It identifies the chapter content container, extracts only readable text (paragraphs, headings, list items), and skips code blocks, tables, figures, and footnotes. The result is clean, natural audio that makes sense — you hear the author's explanations without 'import numpy as np, def train underscore model, open paren, X comma y, close paren, colon' interrupting every other paragraph.
The workflow: open any book on O'Reilly Learning in Chrome or Edge, click the CastReader extension icon, and press play. It reads the current chapter aloud with paragraph highlighting that follows along. When you're done with a chapter, CastReader can auto-advance to the next one. If you scrolled halfway through the chapter before clicking play, it detects your position and starts reading from there — no need to listen from the beginning.
Everything about O'Reilly text to speech
O'Reilly's mobile app has a basic read-aloud feature using your device's built-in TTS. However, it reads everything including code blocks and tables, making it unusable for technical books. The web reader at learning.oreilly.com has no built-in TTS. CastReader adds intelligent TTS that skips code and reads only the prose.
O'Reilly has a small audiobook catalog (a few hundred titles), but the vast majority of their 50,000+ technical books have no audio version. CastReader turns any O'Reilly book into an audiobook using AI text-to-speech.
Install CastReader (free Chrome extension), open any book on learning.oreilly.com, and click the extension icon. CastReader reads the chapter aloud with paragraph highlighting, skipping code blocks and tables automatically.
Yes. CastReader's O'Reilly integration automatically filters out code blocks, inline code, tables, figures, and footnotes. It only reads paragraphs, headings, and list items — the parts that make sense as spoken audio.
Yes. When the current chapter finishes, CastReader automatically clicks the next chapter button and continues reading. You can listen through an entire book hands-free.
Yes — CastReader is free to use, no signup. CastReader Pro (optional) adds premium ultra-realistic voices, more listening hours, voice cloning, and AI document analysis. You're already paying for your O'Reilly subscription — CastReader adds audio on top.
CastReader supports 40+ languages with natural AI voices. Most O'Reilly books are in English, but CastReader automatically detects the language and selects the appropriate voice.
Yes. CastReader works with O'Reilly accessed through library proxies (e.g., EZproxy) and direct access at learning.oreilly.com. It detects O'Reilly's content structure regardless of the access method.
Yes. Scroll to where you want to start, then click play. CastReader detects your scroll position via the URL anchor and begins reading from that point — no need to listen from the beginning of the chapter.
O'Reilly's mobile app read-aloud uses basic device TTS and reads everything on the page including code. CastReader uses AI voices (40+ languages), intelligently skips code/tables/figures, supports paragraph highlighting, auto-advances chapters, and works on the web reader.
Safari Books Online was the former name of O'Reilly Learning Platform. It was renamed in 2019. CastReader works with the current O'Reilly Learning platform at learning.oreilly.com and provides text-to-speech for all books in the library.
CastReader's Send to Phone feature streams audio to your phone via Telegram. Start reading on your computer, tap the phone icon, and continue listening on your phone during your commute.
No, CastReader is designed for text content (books, articles, documentation). O'Reilly video courses already have audio narration.
Conceptual and design-focused books work best — think 'Designing Data-Intensive Applications,' 'Clean Code,' 'The Pragmatic Programmer,' or 'AI Engineering.' Books that are heavy on code examples (like cookbooks or reference manuals) still work but you'll skip more content since CastReader filters out code blocks.
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 — upgrade to CastReader Pro for premium voices, more listening hours, and AI document analysis. Install and start listening to O'Reilly books.
★★★★★ 4.7 · Free to start · No login · Optional Pro