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OST to EPUB converter

Convert OST to EPUB online from any device with a free converter.

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We have already processed 8,914 files with total size of 18,799 Mbytes

About Conversion app

Convert OST files online instantly, no sign-up required. You can convert your OST documents on any platform—Windows, Linux, or macOS. Upload your file, choose the output format, and press convert. When the process is done, your EPUB file will be ready for download.

The OST file's size and structure affect conversion time, though most files are processed in seconds. Advanced features allow you to convert password-protected documents and receive conversion results via email.

No matter where you are, convert your OST documents seamlessly on any device, including smartphones. Available online anytime, this conversion app is completely free for basic scenarios.

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OST

Outlook Offline Storage File

An OST (Outlook Offline Data File) is a file format used by Microsoft Outlook to store a synchronized copy of mailbox data locally, enabling offline access to emails, calendars, contacts, and other items. It is primarily used by Microsoft Outlook and can be accessed or converted using tools like Kernel OST to PST Converter, Stellar Converter for OST, and SysTools OST Viewer. The OST file structure is based on the Messaging Application Programming Interface (MAPI) and supports advanced features like synchronization with Exchange Server, encryption, and data compression for efficient storage and security.

EPUB

Digital E-Book File Format

EPUB (Open eBook File) is a widely used open-standard file format for digital books and publications, designed to be flexible and accessible across various devices. It is supported by most e-readers, such as Kindle, Apple Books, and Adobe Digital Editions, as well as software tools like Calibre for creating and managing EPUB files. The format is based on HTML, CSS, and XML, allowing for reflowable content, embedded fonts, multimedia support, and advanced features like annotations, bookmarks, and accessibility options for visually impaired readers.

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APIs available

Convert popular document and image file formats in your app. The GroupDocs.Conversion APIs are available for .NET, Java, and many other platforms and languages.

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How it works

How to convert OST to EPUB

Step 1
Click inside the file drop area to upload OST file or drag & drop OST file.
Step 2
Click on Convert button. Your OST files will be uploaded and converted to EPUB result format.
Step 3
Download link of result files will be available instantly after conversion.
Step 4
You can also send a link to the EPUB file to your email address.
FAQ

Questions & Answers

Other Supported Conversions

You can also convert OST into many other file formats. Please see the complete list below.

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