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SUN Converter

Turn SUN files into JPG in seconds, straight in the browser. No account, no file size cap. For whole folders and other formats, get reaConverter.

4.8

Over 25 years of experience

Your files never leave your PC

Read what our users say

How to Convert .sun Files in Bulk

1. Install reaConverter

Download reliable SUN conversion software to convert multiple .sun files and folders in one go.

2. Select SUN Files

Select SUNs from a folder or drag and drop them into reaConverter, then choose the desired output format.
reaConverter - Load SUN files

3. Start Conversion

Click Convert to start the bulk conversion of all selected SUN files. The process will begin right away.
reaConverter - Start SUN conversion

Step by step

See It in Action

For quick and effortless SUN file handling on your PC, reaConverter offers powerful conversion tools with batch processing. Best of all, it works entirely offline — ensuring your sensitive data never leaves your computer.

Extra Tools

Do more with your files

Converting SUN files for use in a larger project? reaConverter offers many ways to process files, so you can customize them according to your requirements.

Our range of editing options includes auto-processing options such as auto-rotate, auto-crop, watermarking and more. Change Color Space, copy Metadata, set DPI, manage ICC Profile, control Bit Depth.

Image editing

User reviews

From those who tried it

Average User Rating:
Last updated on June 27, 2026
Our volunteer team uses reaConverter to prepare images for fundraising campaigns. The learning curve was minimal, and the results are professional-grade. The customer support team even helped us customize a workflow — fantastic service!
Jason P. Bailey
Jason P. Bailey
Non-Profit Coordinator
For agencies handling confidential data, reaConverter eliminates cloud-upload risks while delivering unmatched conversion reliability. Our team uses it both in-office and remotely with identical results.
Jamal Bailey
Jamal Bailey
Satisfied Customer
reaConverter is pure gold! Rock-solid performance with zero crashes. No internet needed—perfect for travel or low-connectivity work. The ultimate offline alternative to sketchy web converters. Plus, the desktop version keeps sensitive files secure since nothing ever gets uploaded to the cloud.
Malik T. Martin
Malik T. Martin
Satisfied Customer
An efficient all-in-one solution for image conversion and light editing, designed for maximum user-friendliness.
Elena Anderson
Elena Anderson
Happy User
Enable shell integration for lightning-fast file conversions directly from Windows Explorer.
R. Lewis
R. Lewis
Happy User
An excellent program! I use it regularly in my work - it supports nearly every file format imaginable. The interface is intuitive and runs flawlessly every time.
Roger Cook
Roger Cook
Happy User

Questions & Answers

SUN files: Frequently Asked Questions

Can reaConverter open SUN files?

reaConverter fully supports the SUN file format – open, edit, and export SUN files to any other popular file format with ease.

How do I change SUN to another format?

reaConverter is a user-friendly tool for converting SUN files. Once installed on your computer, it allows you to convert all your .sun files at once with just a few clicks. You can even convert sun images directly from Windows Explorer using the right-click menu — fast and convenient.

Can I convert SUN online?

If you only want to convert a few SUN files, you are welcome to try our free online SUN converter.

How can I turn SUN files on my computer to another format?

The best way to convert SUN files on your PC is to get a quality piece of software, such as reaConverter. This software is extremely efficient in managing a wide range of batch files conversions, including conversion from SUN.

How can I automate SUN files conversion?

reaConverter supports all the essential automation features, such as right-click сonversion and Watch Folders, for the most efficient automated file conversion in any software of its kind.

Can I convert SUN files using scripts or the command-line interface?

reaConverter provides full access to all its features from the Windows command-line shell, including the command-line sun converter.

What else can I do with reaConverter?

Convert DICOM filesCrop photoTrace images to vectorChange bit depthConvert whole-slide images

What formats can I convert a SUN file to?

Discover More

Beyond SUN conversion

Convert .sun files in batches of any size, with editing and processing applied along the way. The same tool also handles 700+ other formats, including CAD, medical imaging, and GIS.

Free trial · Windows 10/11 · v8.0.247 · Files never leave your computer

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