Groupdocs logo
  1. GroupDocs Products
  2. Conversion App
  3. Convert OST to HTM

OST to HTM converter

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

Powered by groupdocs.com and groupdocs.cloud.

drop files here

By uploading your files or using our service you agree with our Terms of Service and Privacy Policy.

We have already processed 5,839,787 files with total size of 9,550,426 Mbytes

About Email converter

Convert OST to HTM files online with our free email converter app. No matter your platform — Windows 10, Mac, Android or iPhone — you can convert OST files rapidly.

Common email-related file formats include MSG, EMLX, and VCF. MSG is used by Microsoft Outlook to store individual email messages with their metadata. EMLX is a similar format used by Apple Mail for single email files. VCF (vCard) is used for storing contact information.

To change OST to HTM, simply upload your OST file, choose a target format, and click Convert. Once done, your file will be ready to download instantly.

Check our video
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.

HTM

Hypertext Markup Language File

HTM is a file format used to create and structure content for web pages, defining elements like text, images, and links. It can be opened and edited using text editors like Notepad or specialized tools like Visual Studio Code, Adobe Dreamweaver, or web browsers for rendering. The format uses tags enclosed in angle brackets to define elements, supports CSS for styling, JavaScript for interactivity, and can include multimedia, making it the foundation of modern web development.

Add the conversion API to your app

  • Convert over 200 file formats — including PDF, Word, Excel, HTML, images, and many more
  • Load files from disk, URLs, FTP servers, or cloud storage (such as Amazon S3 or Azure)
  • Customize output settings — rotate and reorder pages, add comments, or apply watermarks
How it works

How to convert OST to HTM

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 HTM 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 HTM 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.

© Aspose Pty Ltd 2001-2025. All Rights Reserved.
More apps

Upgrade to Premium

The application usage limit reached.
Upgrade for extended access, starting at $4/month.
Upgrade Learn more