Free · Private · In your browser

AZW3 Reader

Open a modern Kindle AZW3 (or MOBI) and start reading straight away, right in your browser. Nothing is uploaded, ever.

Files never uploaded Works offline Free, no signup No file size limits

How it works

  1. Drop your AZW3 or MOBI book into the box above.
  2. It opens instantly, rendered right here in your browser – no upload, because nothing is sent anywhere.
  3. Read with adjustable text size and a chapter list. Close the tab and nothing is left behind.

Why “no upload” matters

Every conventional converter site works the same way: your file travels to their server, sits in their queue, gets converted on their hardware, and – you hope – gets deleted afterwards. You can’t verify any of it. The FBI has even warned about free converter sites that use that upload as a way to deliver malware or harvest the documents themselves. Your books are yours; a format change shouldn’t require handing them to a stranger.

ebook.tools removes the question entirely. The converter is delivered to your browser as code and runs on your machine; the file you drop is opened from memory, transformed, and saved back – the network isn’t involved at all. That isn’t a policy promise, it’s an architecture, and you can test it: load this page, switch off your wifi, and convert. It works exactly the same, because there was never anything to send.

A private AZW3 reader that never sends your Kindle books away

AZW3, also called KF8, is the format modern Kindle books use: the .azw3 and .azw files you sideload, and the ones apps like Calibre and Kindle Previewer produce. It is richer than the old MOBI it replaced, with proper CSS and structure, but it is still awkward to open outside the Kindle world. This reader opens it entirely on your own machine, the same way every tool on ebook.tools works, so the book never travels anywhere.

Opening a file here reads its spine and table of contents and shows one chapter at a time, with a contents list you can jump around in. Text resizes to whatever is comfortable, the layout reflows to your screen, and it follows your system’s light or dark theme. Older MOBI files open on this same page, so you do not need to know which flavour of Kindle format you were handed.

The privacy is enforced, not promised. A Kindle book is really a bundle of HTML, and HTML can carry scripts, tracking pixels and links that reach out to the network. Every chapter renders inside a locked-down sandbox with scripting off and no network access at all: images and styles that live inside the book are inlined so it looks right, while anything that would phone home is stripped before it reaches the page.

The honest caveats. DRM-locked purchases from the Kindle Store cannot be opened, because we never strip DRM; we detect it and say so. If you want a copy that opens everywhere, the AZW3 to EPUB converter makes a clean EPUB on your device, ready for the EPUB reader. Working with older files? The MOBI reader covers those too.

Frequently asked questions

What is the difference between AZW3 and MOBI here?
They are two generations of the Kindle format, and this reader opens both. AZW3 (KF8) is the newer, richer one; MOBI is the older one. Drop either and it renders the same way, so you do not need to tell them apart.
Is my AZW3 uploaded anywhere?
No. It is opened and rendered by your own browser, with nothing sent to a server. Open one book, turn on airplane mode, and open another: it still works, which is the proof there was never an upload.
Can the book run scripts or track me?
No. Each chapter renders inside a sandbox with scripting disabled and no network access. In-book images and styles are inlined so the page looks right, and anything that would reach the internet is removed first.
My .azw from Amazon will not open. Why?
A file downloaded through the Kindle app or Send to Kindle is usually DRM-protected and tied to your account. We never remove DRM, so we detect it and tell you. DRM-free AZW3 and AZW files open normally.
Should I just convert to EPUB instead?
If you want the widest compatibility, yes. The AZW3 to EPUB converter runs on your device and hands the result to the EPUB reader. For a quick read of a Kindle file you already have, opening it directly here is faster.