“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.”
Listen to AO3 Fanfiction
Turn any Archive of Our Own fic into natural-sounding audio. Open it in Chrome, click CastReader, and listen while commuting, cooking, or doing chores.
Why Listen to AO3 with CastReader?
Consume more fanfiction without eye strain
Any Fic, Any Chapter
Open any AO3 work — any rating, any fandom — and click the CastReader icon. It reads the chapter aloud immediately with natural AI voices.
Reads the Fic, Not the Tags
CastReader extracts the story text and skips tags, author notes, kudos, comments, and navigation. You hear only the story.
Paragraph Highlighting
Each paragraph highlights as it's read aloud. Click any paragraph to jump there. Perfect for 100K+ word epics.
Free Tool for a Free Platform
AO3 is free. CastReader is free to use, no signup. Upgrade to CastReader Pro for premium voices, more listening hours, and AI document analysis.
Frequently Asked Questions
Everything you need to know about listening to AO3 fanfiction
How do I listen to AO3 fanfiction?
Install CastReader from the Chrome Web Store (free, no account needed). Open any AO3 work, click the CastReader icon in your toolbar, and it reads the chapter aloud with natural AI voices.
Does AO3 have a built-in text-to-speech feature?
No. AO3 does not have any built-in TTS feature. You can use CastReader to read any AO3 fic aloud directly in your browser.
Does it skip tags, author notes, and comments?
Yes. CastReader's extraction algorithm identifies the story text and skips everything else — tags, notes, kudos, bookmarks, comments, and navigation.
Does it work with the entire work view?
Yes. Whether you're reading chapter by chapter or the full work view, CastReader extracts and reads the story text.
Is it 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.
Can I control playback speed?
Yes. Adjust speed from the floating player. Many readers use 1.5x or 2x for long fics.
Does it highlight text as it reads?
Yes. The current paragraph is highlighted and the page auto-scrolls to follow along.
Does it work on Edge?
Yes. CastReader is available on both Chrome and Edge.
Listen on Your Phone
Download the CastReader app to listen to your uploaded documents anywhere.



Why TTS Matters in 2026
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 →What Readers Say — Including the Critical Reviews
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.
“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.
Recent Updates
We re-test, re-write, and ship continuously. Every entry has a real date.
Site-wide trust signals refresh
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.
Send-to-Phone reliability improvements
Telegram audio streaming now auto-turns pages reliably across Kindle Cloud Reader and Apple Books. Reduces session interruptions by ~70% in internal testing.
Technical deep-dive published
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.
CastReader for Mac released
Native macOS app reads Kindle for Mac with word-level highlighting. Floating player + system-wide hotkeys. No browser needed.
Featured on Product Hunt
Ranked #10 in Daily, 99 upvotes, 4 community comments shaped the v1.2 roadmap.
Voice quality upgrade — Kokoro AI
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).
First wave of extraction reliability improvements
OCR success rate improved from 78% to 89% on English-language Kindle books. Multi-column page detection added for academic PDFs.
Why This Exists
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
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★★★★★ 4.7 · Free to start · No login · Optional Pro