What Is a .azw File? .azw Format, MIME & How to Open

Quick facts

Extension.azw

File typeKindle Ebook

MIME typeapplication/vnd.amazon.ebook

CategoryData & Text

Charset—

Compressible—

Format familyebook

What is .azw

What is a .azw file?

A .azw file is a Kindle Ebook — Amazon Kindle ebook format.

In the mime-db registry it maps to application/vnd.amazon.ebook. When serving .azw over HTTP, set the Content-Type header as shown in Developer info below.

Related entities: it maps to application/vnd.amazon.ebook — and is delivered over HTTP via the Content-Type header.

How to open .azw files

Use Kindle or Calibre to open and edit .azw files.
Any text editor (Notepad, VS Code) can inspect the raw content as text.

Developer info

When served over HTTP, responses should set the following header:

Content-Type: application/vnd.amazon.ebook

Common software that reads/writes .azw:

KindleCalibre

Relation chain

.azwextension of

format

ebookserved as

mime type

application/vnd.amazon.ebooksent via header

http header

Related extensions

Related MIME types

application/vnd.amazon.ebook

.azw

Common uses

Configuration files
Data interchange between systems
API request and response payloads
Logs and data exports

How to edit .azw files

Open the file with Kindle, make your changes and save.
Most editors preserve the original formatting and encoding — avoid changing the charset.

How to create .azw files

Create a new file and save it with the .azw extension, or export this format from Kindle.

Frequently asked questions

What programs can open .azw files?

Common options include Kindle, Calibre. You can also open many of these files with built-in viewers or a browser.

How do I create a .azw file?

Create a new file in any text editor or the app that owns the format and save it with the .azw extension.

What is the relationship between .azw and the application/vnd.amazon.ebook MIME type?

application/vnd.amazon.ebook is the media type identifier used for .azw files during network transfer (for example in the HTTP Content-Type header).

Sources & standards

Updated 2026-08-18

Explore this reference

What is a .azw file?

What programs can open .azw files?

How do I create a .azw file?

What is the relationship between .azw and the application/vnd.amazon.ebook MIME type?

Related extensions

Related MIME types

Related headers

Related methods

Related status codes