“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.”
Turn Any Document Into Speech
Listen anywhere — browser, phone, or desktop.
CastReader works on every device. Pick yours and start listening in 30 seconds.
★★★★★ 4.7 · Free to start · No login · Optional Pro
One Converter for Every Document You Need Read Aloud
PDFs, Word files, EPUBs, plain text — drop them in and listen. No format juggling, no install.
Every Common Format
PDF, Word, EPUB, Text — All in One Place
Stop hunting for a different converter for each file type. CastReader handles PDF, DOCX, EPUB, TXT, Markdown, and HTML in a single tool. Drop the file in and it figures out the format, pulls the text, and reads it. No exporting, no converting between formats first.
Layout-Aware
It Reads Structure, Not Soup
Documents are full of things you don't want spoken: headers, footers, page numbers, footnotes, multi-column layouts. CastReader detects the structure of each file, reads in the order a human would, and strips the furniture. A two-column report and a clean Word doc both come out as listenable narration.
Natural Voice
Comfortable for Long Files
A neural voice model carries the reading — rhythm, pauses, and emphasis that hold up across a long chapter or report instead of collapsing into a monotone after a sentence. Adjust the speed to suit study or skimming, and download the finished audio as an MP3.
Browser-Only
No Office, No Acrobat, No Install
You don't need Microsoft Word to read a DOCX, or Acrobat to read a PDF, or Calibre to read an EPUB. This page reads them all with nothing installed. It runs on a Chromebook, a managed laptop, or a phone — wherever a browser opens.
Converting a Document to Speech, Whatever the File Type
Documents arrive in a mess of formats. A research paper is a PDF, a report is a Word file, a book is an EPUB, your notes are plain text or Markdown, and an article you saved is HTML. When you want to listen instead of read, the usual answer is a different tool for each one — a PDF reader here, a DOCX converter there, an EPUB app somewhere else — each with its own quirks, limits, and paywall. The friction is enough that most people give up and just read on screen, even when listening would be easier.
CastReader collapses that into one converter. Drop in a PDF, DOCX, EPUB, TXT, Markdown, or HTML file and it detects the format, extracts the text, and reads it aloud. You don't export anything, you don't convert one format into another first, and you don't need the original application installed — no Word for the DOCX, no Acrobat for the PDF, no Calibre for the EPUB. The whole thing runs in the browser after a single click.
Getting the text out cleanly is the part most tools skip, and it's where the difference shows. A document is not a flat string of words; it has columns, headers, footers, page numbers, footnotes, and captions, and a naive extractor reads all of it in storage order. CastReader detects the structure of each file, reads in the order a person would, and removes the furniture that should never be spoken. What reaches the voice is the actual content, in the right sequence. The voice itself is a neural model that stays comfortable to listen to across a long file, not a robotic reader that wears thin after a paragraph.
The people who lean on this share one thing: a stack of documents and not enough screen time. Graduate students convert a week's reading into something they can absorb on the move. Professionals turn a long report into audio for the commute. People with dyslexia or low vision get a clean spoken version of files that are hard to read by eye. Anyone proofing their own writing catches awkward sentences by hearing the document read back. The format of the file stops mattering once you can just press play.
On cost, the document-conversion category is full of per-feature paywalls — pay for PDF here, pay for upload there, pay again to remove a watermark. CastReader is free to use with no signup to get started, and the same tool covers every supported format. If you want premium voices, more listening hours, and AI document analysis, CastReader Pro is the optional upgrade; a two-page file and a five-hundred-page one are otherwise handled the same way.
For documents you open inside the browser anyway — papers in a database, files in cloud drives, docs shared as links — the free CastReader Chrome extension reads them in place without a download-and-upload round trip. It speaks the content directly in the tab, highlights each line as it reads, and remembers where you left off. The converter on this page is ideal for files on your device; the extension is what you want for documents you read in the browser.
Document to Speech — FAQ
Common questions about converting documents to audio
What document formats can I convert to speech?+
PDF, EPUB, DOCX (Word), TXT, Markdown (.md), and HTML. Drop any of them in and CastReader detects the format, extracts the text, and reads it aloud — no need to convert between formats first or have the original app installed.
Is converting a document to speech free?+
Yes. Upload a file or paste text, choose a voice, and listen — no account needed to get started and nothing to install. The free tier covers everyday use; CastReader Pro is an optional upgrade for premium voices, more listening hours, and AI document analysis. The same tool handles every supported format, with no per-format paywall.
Do I need Microsoft Word, Acrobat, or Calibre installed?+
No. CastReader reads DOCX without Word, PDF without Acrobat, and EPUB without Calibre. Everything runs in your browser, so it works on Chromebooks and locked-down work or school machines where you can't install software.
Does it handle multi-column PDFs and complex layouts?+
Yes. CastReader detects the structure of each document — columns, headers, footers, footnotes — reads in the order a person would, and strips out the parts that shouldn't be spoken, like page numbers and figure captions. A two-column report comes out as clean narration.
Can I download the audio as an MP3?+
Yes. After your document is processed, play the audio in the browser or download it as an MP3 for offline listening on your phone, in the car, or in any audio player. Long documents are split into tracks you can play or download independently.
What languages are supported?+
Over 40. CastReader auto-detects the language of your document and selects a native-sounding voice. This makes it useful for foreign-language material and for language learners who want to listen along while they read.
How long can my document be?+
Long documents are supported — the system processes them section by section, turning each into an audio track you can play or download on its own. Most files process quickly; a very large book may take a minute or two.
Is my document private and secure?+
Yes. Your file is processed only to extract text and generate audio, and the result is available only to you. We don't share, sell, or train on your documents, and no required account means no profile tracking your reading.
A document not converting cleanly? Send it to our debug team
More Document & Listening Tools
PDF to Audiobook
Convert a whole PDF into a downloadable audiobook — multi-column, scans, math
EPUB to Audiobook
Turn EPUB ebooks and other formats into natural-voice audio
Text to Speech Online
Paste any text and hear it spoken in a natural AI voice — free, no signup
Free Text to Speech
The classic free TTS tool — paste text, pick a voice, listen
为什么 TTS 在 2026 年值得做
硬数据 —— 不是 vibe —— 来自权威来源
effect size 0.35
22 篇研究的 meta 分析显示 TTS 对阅读障碍学生的理解力提升幅度(Wood, Moxley, Tighe & Wagner, Journal of Learning Disabilities, 2018)
Source →读者怎么说 —— 包括给我们打低分的评论
下方每一条 Chrome Web Store 评论都可以在卡片链接处验证。我们不藏负面反馈 —— 我们 24 小时内回复。
“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
CastReader 创始人 Yan Xu 48 小时内回复:承认问题,下个版本上线了 bookmark 功能。这条评论的反馈直接推动了 v1.2 路线图。
“Need to highlight text and select it.”
“Hard to select text.”
↪ Founder reply
CastReader 创始人 Yan Xu 24 小时内回复:道歉、询问发生的网站/浏览器、提供键盘快捷键作为绕过方案、留下 support@castreader.ai 直接支持邮箱。
近期更新
我们持续测试、改写、上线。每条更新都带真实日期。
全站信任信号刷新
用 verbatim Chrome Web Store testimonial、真实有声书市场数据、12 工具实测的 methodology 重写落地页。每条主张都有来源链接。
发送到手机可靠性提升
Telegram 音频流现在能稳定自动翻页,覆盖 Kindle Cloud Reader 和 Apple Books。内部测试显示会话中断减少约 70%。
技术深度文章发布
写了 OCR 管线的深度文章:CastReader 如何处理 Amazon 每本 Kindle 书 184 套随机字母表和 361 个独特 glyph。发表在 dev.to。
CastReader for Mac 发布
原生 macOS 应用,朗读 Kindle for Mac,词级高亮。浮窗播放器 + 系统级快捷键。不需要浏览器。
登上 Product Hunt
Daily 榜 #10,99 upvotes,4 条社区评论推动了 v1.2 路线图。
语音质量升级 —— Kokoro AI
从旧 TTS 引擎切换到 Kokoro 神经网络语音。用户评论从 'usable but robotic' 转为 'enjoy listening for hours'(来自 patrick chiang 的 Chrome Web Store 评论原话)。
提取可靠性首轮提升
英文 Kindle 书的 OCR 成功率从 78% 提升到 89%。加入了多栏页面检测(学术 PDF 适用)。
为什么有这个产品
我做 CastReader 是因为我有几百本 Kindle 书,想在晨跑时听它们,但不想为每本再买 Audible 版。技术问题 —— Amazon Cloud Reader 的字体加密 —— 最后用 OCR 解决了。产品问题 —— 让它在手机、桌面、40+ 语言上真正好用 —— 花了两年迭代。我们是个小团队。我亲自回复每一条 Chrome Web Store 评论(上方 testimonials 里有证明 —— 包括 3 星和 1 星的)。如果有什么坏了或缺失,邮件 support@castreader.ai。
—— Yan Xu, 创始人
最近审阅: · CastReader 团队 —— 基于 2025 测试数据
Read documents out loud on every device — browser, phone, or desktop.
Free CastReader works on Chrome / Edge / iOS / Android / Mac. Turn any document into speech, no install required.
★★★★★ 4.7 · Free to start · No login · Optional Pro


