Don't just read it aloud — have it explained
Read & Explain talks you through any page in the language you know best, while a pen circles and underlines the key points on the original text. Eyes on the page, ears on the explanation.
Free · 40+ languages · Works on any website
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Like a teacher with a pen — talking you through the text while circling and underlining what matters. That is Quickread.
Reading a page in another language? Quickread explains it in the language you know — same pen, same mark-up.
Read aloud vs. Read & Explain
Every other TTS tool stops at reading the words. Explain goes further.
- Reads the original text, word for word
- Same language as the page
- Paragraph-level highlight
- You still have to make sense of it yourself
- Explains what the page means, in plain language
- Your own language — even for foreign pages
- A pen circles & underlines the exact key points
- Like a teacher reading along beside you
Three things at once — like a teacher pointing at the page
Explanation, pen marks, and subtitles, all synced to the audio.
Explains, not just reads
Instead of reading the original sentence by sentence, it summarizes and unpacks the meaning — so dense, technical, or foreign pages finally click.
Marks the key points
A pen moves across the original, circling, underlining, and highlighting exactly what matters. Your eyes follow the moving pen, so you never drift off.
Subtitles you can follow
Every explanation appears as a synced subtitle, word by word, so you read and listen at the same time — dual-channel focus that fights distraction.
Reads any language — explains in yours
Reading an English paper, a French article, or a Japanese page? Read & Explain understands the original and explains it in the language you know best — so a page you couldn't read becomes one you understand.
How to use Read & Explain
Three steps, no setup.
Install the extension
Add CastReader to Chrome or Edge — free, no signup.
Open any page
An article, a research paper, a foreign-language site, even your Kindle book.
Click Explain
Tap the 🎧 button and choose Explain. Sit back and follow the moving pen.
When Read & Explain shines
Anywhere the words alone aren't enough.
Dense academic papers
Get the gist of a research paper — and its key claims — before committing to read it in full.
Foreign-language pages
Read news, blogs, or docs in another language, explained in yours.
Long articles
Turn a 20-minute read into a guided walkthrough of the points that matter.
Studying & learning
Hear concepts explained, not just read aloud, so they actually stick.
Language learners
See the original, hear the meaning, and follow the pen — all at once.
Technical docs
Cut through jargon-heavy documentation far faster.
Read & Explain — Questions
What's the difference between Read Aloud and Read & Explain?▾
Read Aloud reads the original text out loud, word for word. Read & Explain instead explains what the page means — in your own language — while a pen marks the key points on the original. One reads it to you; the other teaches it to you.
What language does it explain in?▾
It explains in your language, auto-detected from your browser, and you can override it in settings (pick a specific language, or follow the original). The page itself can be in 40+ languages — English, Chinese, Japanese, Spanish, French, German and more.
Can it explain a page written in a language I don't read?▾
Yes — that's the whole point. Open a page in any supported language and Read & Explain will walk you through it in the language you know, marking the key spots on the original as it goes.
How is this different from an AI summary tool?▾
A summary hands you a block of text. Read & Explain is a guided, spoken walkthrough: it talks you through the page while a pen circles and underlines the exact spots on the original, so you stay anchored to the source instead of trusting a detached summary.
Does it work on Kindle, WeRead, or PDFs?▾
Yes. It works on ordinary web pages and on rendered readers like Kindle Cloud Reader and WeRead — it reads what's on screen, then explains it. On paginated readers it explains the page you're currently on.
Will the pen marks cover the text?▾
No. The pen uses light highlights, underlines, and circles that sit over the original without hiding it — just like marking up a printed page with a highlighter.
Is it free?▾
Yes. CastReader is free to install and use, and Read & Explain is included. No signup required.
Which browsers are supported?▾
Chrome, Edge, and other Chromium-based browsers (Brave, Arc, and more). A native Mac app is also available.
Try Read & Explain on your next long read
Install CastReader, open any page, and let it explain — free, no signup.